                        Docket No. 98712.

                        IN THE
                   SUPREME COURT
                          OF
                 THE STATE OF ILLINOIS



SOUTHERN ILLINOISAN, Appellee, v. THE ILLINOIS
             DEPARTMENT OF PUBLIC HEALTH et al.,
Appellants.

                 Opinion filed February 2, 2006.



     JUSTICE McMORROW delivered the judgment of the
court, with opinion.
     Chief Justice Thomas and Justices Freeman, Fitzgerald,
Kilbride, Garman and Karmeier concurred in the judgment and
opinion.



                             OPINION

     Plaintiff, the Southern Illinoisan newspaper, requested the
Illinois Department of Public Health (Department) to release from the
Illinois Health and Hazardous Substances Registry (Cancer Registry)
certain data about incidents of neuroblastoma, a rare form of
childhood cancer. The Department denied plaintiff=s request.
Thereafter, plaintiff filed a complaint in the circuit court of Jackson
County pursuant to the Freedom of Information Act (FOIA) (5 ILCS
140/1 et seq. (West 1998)), requesting judicial review of the
Department=s denial. The circuit court granted plaintiff summary
judgment and ordered the Department to release the requested data.
The appellate court reversed the judgment of the circuit court and
remanded the cause for further proceedings. 319 Ill. App. 3d 979
(2001) (Southern Illinoisan I). After a bench trial, the circuit court of
Jackson County again ordered the release of the requested
information. The appellate court affirmed the judgment of the circuit
court and directed the Department to release the information
requested by plaintiff. 349 Ill. App. 3d 431 (Southern Illinoisan II).
For the reasons that follow, we affirm the judgment of the appellate
court.

                           BACKGROUND
     We limit our discussion of the factual background and
procedural history of the instant cause to only those points relevant to
the issue presented in this appeal. Plaintiff, the Southern Illinoisan, is
a daily newspaper published in Carbondale, Illinois. On October 28,
1997, plaintiff made a written request, pursuant to the FOIA (5 ILCS
140/3 (West 1998)), that the Department provide plaintiff with copies
of documents relating to the incidence of neuroblastoma 1 in Illinois
from 1985 to the date of the request. In its request, plaintiff wrote that
it believed that these documents were Aavailable by type of cancer,
zip code and date of diagnosis,@ and asked that the information be
delivered to plaintiff in that format. Plaintiff did not request that the
Department release any other identifying information, such as the
patients= names or addresses. In a letter dated November 18, 1997, the
Department denied plaintiff=s FOIA request. The Department based
this denial on sections 7(1)(a) and (1)(b) of the FOIA (5 ILCS
140/7(1)(a), (1)(b) (West 1998)), which protects information that is
specifically exempted from disclosure under state law. According to
the Department, the Medical Studies Act (735 ILCS 5/8B2101 (West

   1
    Neuroblastoma is a cancer of the peripheral nervous system that
typically develops in infants and young children. Statistics reveal that
neuroblastoma afflicts approximately 9 out of every 1 million children born.
See Donaldson v. Central Illinois Public Service Co., 199 Ill. 2d 63, 66
(2002).




                                   -2-
1998)) prohibited the Department from disclosing any information
Acollected in a medical study.@
     On November 24, 1997, plaintiff appealed the denial of its FOIA
request to Dr. John R. Lumpkin, the Director of the Department.2 In a
letter dated December 4, 1997, Dr. Lumpkin reaffirmed the denial of
plaintiff=s FOIA request. In his letter to plaintiff, Dr. Lumpkin
explained the basis for the denial: AAfter reviewing the request, I
must affirm the Department=s denial of the information regarding the
incidence of neuroblastoma by zip code and date of diagnosis based
on the Medical Studies Act (735 ILCS 5/8B2101). I believe this
information is, and should continue to be, protected as it is
information collected in a medical study.@
     On January 23, 1998, plaintiff filed a complaint in the circuit
court of Jackson County, pursuant to section 11 of the FOIA (5 ILCS
140/11 (West 1998)). The complaint requested, inter alia, judicial
review of the Department=s denial of plaintiff=s information request.
Plaintiff contended that no statutory disclosure exemption applied to
the records it had requested from the Department. According to
plaintiff, the records it sought to obtain from the Department under
the FOIA were clearly of significant interest to the general public, as
they would Areveal the existence or non-existence of cancer clusters
in the State of Illinois.@ In support of its request for disclosure,
plaintiff cited to the appellate court=s decision in May v. Central
Illinois Public Service Co., 260 Ill. App. 3d 41 (1994), as controlling.
     On June 8, 2005, plaintiff filed in the circuit court a motion for
judgment on the pleadings or, in the alternative, a motion for partial
summary judgment. According to plaintiff, the Department, in its
answer to plaintiff=s complaint, failed to raise any statutory
exemption as an affirmative defense to plaintiff=s FOIA request for
disclosure. In addition, plaintiff asserted, the Department had failed
to raise any factual basis in support of the claim that the documents
were exempt from disclosure. Plaintiff argued that the instant cause
was factually analogous to the appeal in May, wherein the appellate

   2
   The Department notes that its current Director is Dr. Eric E. Whitaker,
who immediately succeeded Dr. Lumpkin in that post.




                                  -3-
court upheld the trial court=s order directing the Department to
disclose records identical to those requested in this cause. Plaintiff
noted that in May, the court held that the release of the records from
the Cancer Registry by type of cancer, date of diagnosis and ZIP code
would not result in an invasion of patient privacy. Accordingly,
plaintiff asserted, a similar result was warranted here, and there
existed no genuine issue of material fact to preclude entry of
summary judgment in its favor.
     Thereafter, the Department filed a response to plaintiff=s
summary judgment motion, as well as its own cross-motion for
summary judgment. 3 The Department argued, inter alia, that because
disclosure of the information sought by plaintiff was prohibited by
the Illinois Health and Hazardous Substances Registry Act (Registry
Act) (410 ILCS 525/1 et seq. (West 1998)), it was therefore exempt
under section 7(1)(a) of the FOIA (5 ILCS 140/7(1)(a) (West 1998)).
The Department explained in its pleadings that it could not satisfy
plaintiff=s FOIA request because although the FOIA provides that
Aeach public body shall make available to any person for inspection
or copying all public records@ (see 5 ILCS 140/3(a) (West 1998)),
there are certain exceptions to disclosure, including A[i]nformation
specifically prohibited from disclosure by *** State law or rules or
regulations adopted under *** State law@ (see 5 ILCS 140/7(1)(a)
(West 1998)). The Department argued that the information requested
by plaintiff was prohibited from disclosure under this provision
because the Registry Act precludes disclosure of information which
reveals A[t]he identity, or any group of facts which tends to lead to the

   3
     On the date it filed its response, the Department also filed a motion to
file an amended answer. The Department requested the court to allow it to
amend its answer to reflect the affirmative defenses raised in the
Department=s response to plaintiff=s summary judgment motion and in its
own cross-motion for summary judgment.




                                    -4-
identity, of any person whose condition or treatment is submitted to
the Illinois Health and Hazardous Substances Registry.@ See 410
ILCS 525/4(d) (West 1998).
     In support of its position, the Department attached the affidavit
of Dr. Latanya Sweeney, Ph.D., a professor of computer science and
public policy at Carnegie Mellon University. In her affidavit, Dr.
Sweeney attested that, at the behest of the Department, she conducted
an experiment to determine if persons listed in the Cancer Registry
could be identified from only the three information fields requested
by plaintiff: the type of cancer, the date of diagnosis, and the patient=s
ZIP code. According to Dr. Sweeney, she compared the data in these
three information fields to other data sets that are available to the
general public, such as patient names, addresses, phone numbers,
financial information, and other medical information. Even though
the data in the Cancer Registry did not have identifiers such as
names, addresses and telephone numbers, Dr. Sweeney attested that
through her experiment she could Ashow how persons can be re-
identified from the Illinois Cancer Registry when the combination of
data elements that includes only type of cancer, date of diagnosis, and
zip code is provided.@ According to Dr. Sweeney, her experiment
Aestablishe[d] that a significant number of individuals in the general
public with access to a personal computer, using traditional database
software, who purchase or acquire public data sets will be able to
reidentify individuals in the Illinois Cancer Registry,@ as this
Aseemingly anonymous information can be re-identified by linking
the information to databases that are made available to the public.@
     Finally, although the Department noted that plaintiff relied upon
the May case, and also acknowledged that in May the court was faced
with the same issue as in the instant matter, the Department attempted
to draw one crucial difference between May and the instant cause: the
court in May was not presented with any definitive showing of how
the data contained in the Cancer Registry could be reidentified. The
Department asserted that, based upon Dr. Sweeney=s affidavit, it
established how the dissemination of this information could tend to
lead to a patient=s identity, and, therefore, that the disclosure of the
information was prohibited.
     On December 31, 1998, the circuit court granted plaintiff=s
motion for summary judgment, and denied the Department=s cross-


                                  -5-
motion for summary judgment. In the course of its ruling, the court
noted that it had made an in camera inspection of the records
requested by plaintiff under the FOIA and determined that the
appellate court=s decision in May was controlling. Accordingly, in its
order, the circuit court directed the Department to Aproduce the
Illinois Cancer Registry by listing the type of cancer, date of
diagnosis and zip code of each cancer patient from 1985 to present.@
The circuit court also ordered that the parties were Arestricted from
identifying or attempting to identify or contact cancer patients from
information produced pursuant to this action.@ On July 22, 1999, the
circuit court denied the Department=s motion for reconsideration.
      On appeal, the appellate court reversed the circuit court=s grant
of summary judgment to plaintiff. 319 Ill. App. 3d 979 (2001)
(Southern Illinoisan I). Relevant to the instant appeal, the Department
had argued, inter alia, that the disclosure exemption in section 7(1)(a)
of the FOIA (5 ILCS 140/7(1)(a) (West 1998)), which exempts from
release information specifically prohibited from disclosure by federal
or state law, precluded the release of the information requested by
plaintiff. The Department asserted that disclosure of the information
requested by plaintiff would violate section 4(d) of the Registry Act
(410 ILCS 525/4(d) (West 1998)), which provides that the Aidentity,
or any group of facts that tends to lead to the identity, of any person
whose condition or treatment is submitted@ to the Cancer Registry is
confidential and not open to public inspection or dissemination. The
appellate court agreed with the Department that there was a genuine
issue of material fact as to this issue.
      Although plaintiff argued that Dr. Sweeney=s affidavit was
conclusory, the appellate court disagreed. The appellate court held
that Dr. Sweeney=s affidavit raised a genuine issue of material fact,
namely: AIs the requested data that which tends to lead to the identity
of any person whose condition is submitted to the Department?@ 319
Ill. App. 3d at 986. The appellate court held that in answering this
question, the circuit court was to read in a Areasonableness@
requirement in determining whether the requested information
constituted a Agroup of facts which tends to lead to the identity@ of
cancer patients, within the meaning of section 4(d) of the Registry
Act. The appellate court explained its reasoning as follows:



                                  -6-
             AThe phrase >group of facts that tends to lead to the
         identity= must mean any group of facts that reasonably
         would tend to lead to the identity of specific persons. The
         entire purpose of the Cancer Registry Act (see 410 ILCS
         525/2(b), (c) (West 1998)) would be effectively repealed by
         subsection 4(d) if we did not impose the reasonableness
         requirement, because any fact, no matter how unrelated to
         identity can tend to lead to identity, and, therefore, any and
         every fact would be exempt under subsection 4(d). However,
         since one purpose of the Cancer Registry Act is to provide
         information to the public, this cannot be what the legislature
         intended. If, however, one reads the statutory phrase as
         precluding the release of information that reasonably would
         tend to lead to identity, some information is exempt, while
         other information is not exempt. In our judgment, whether
         the information sought in this case would reasonably tend to
         lead to the identity of particular individuals presents a
         question of fact.@ (Emphases in original.) 319 Ill. App. 3d at
         987.
     Because the appellate court found that a genuine issue of
material fact was presented, it therefore held that the trial court erred
in entering summary judgment in favor of plaintiff. Accordingly, the
appellate court remanded this cause to the trial court for further
proceedings. 319 Ill. App. 3d at 987.
     Upon remand, the circuit court held a bench trial on June 6,
2002. Because the FOIA places the burden of proof upon the public
body to establish that its refusal of disclosure is in accordance with
the FOIA (5 ILCS 140/11(f) (West 1998)), the Department put on its
case first. The Department=s first witness was Janice Snodgrass, the
manager of the Cancer Registry. She testified that the Cancer
Registry is a Acancer database surveillance system,@ meaning that it
contains information that has been reported to the Department
pursuant to the Registry Act from approximately 400 different
reporting sources. The Registry Act requires mandated reporting of
cancer cases from all Illinois hospitals, as well as from ambulatory
surgical centers and free-standing radiation treatment centers. In
addition, there is voluntary reporting by some physicians,
dermatologists, and pathology labs. Also, Snodgrass testified, there is


                                  -7-
data exchange from 13 other states where Illinois patients might have
migrated.
     Snodgrass testified that the Cancer Registry is maintained on a
computer, and the information in the Registry consists of
demographic information that identifies the patient, including his or
her address, the patient=s county of residence, the patient=s race and
gender, and whether the patient used alcohol and/or tobacco. The
Cancer Registry also contains patient medical information, including
the patient=s type of cancer, how it was diagnosed, the date of
diagnosis, how much it has spread, and treatment and survival
information.
     Snodgrass testified that although the very specific information
contained within the Cancer RegistryBsuch as patient identity and
residenceBis kept strictly confidential, a public data set from the
Cancer Registry is available on the Department=s Web site. This
public data set contains very limited information, and provides this
information at the state, county and ZIP code levels. According to
Snodgrass, as the geographical areas become smaller, less
information is available to protect patient confidentiality. Although
the Department provides public data sets of information from the
Cancer Registry, Snodgrass testified that plaintiff=s request for
information was problematic because plaintiff asked that the
Department disclose the specific number of neuroblastoma cases,
along with date of diagnosis and the patient=s ZIP code. According to
Snodgrass, the public data sets do not specifically disclose whether a
certain case is a neuroblastoma case. Snodgrass testified that if an
individual wishes to obtain information beyond that which is
available in the public data set, the Registry Act provides that the
requestor must fill out an application for access to the data, as well as
sign a confidentiality agreement. The application is then processed by
an internal review board, which then determines whether disclosure
will be made. According to Snodgrass, plaintiff did not avail itself of
this procedure.
     On cross-examination, Snodgrass was asked if she was aware of
recent occurrences of claims of neuroblastoma caused by site-specific
environmental causes. She responded Ayes@ to this question.
Snodgrass testified, however, that the raw data is not information
which is available to the public. A scientist or researcher, however,


                                  -8-
could request this information from the Department if the purpose for
the request was to perform an investigation.
     The Department=s secondBand finalBwitness at trial was Dr.
Latanya Sweeney. Dr. Sweeney testified that she is an assistant
professor of computer science and public policy at Carnegie Mellon
University, and also the University=s director of the Laboratory for
International Data Privacy. Dr. Sweeney joined Carnegie Mellon in
1998, and, prior to that, she worked as an instructor at Harvard
University. Dr. Sweeney stated that she has an undergraduate degree
in computer science from Harvard University, a master=s degree in
computer science and electrical engineering from MIT, and a Ph.D in
computer science from MIT. Dr. Sweeney testified that she has
served as an expert witness in numerous cases involving data privacy
questions and the anonymity of data, and that she has worked as a
consultant for several governmental agencies. Based upon her
credentials, the circuit court qualified Dr. Sweeney as an expert
witness on the subject of data anonymity.
     Dr. Sweeney testified that she was contacted by the Department
in 1998, and asked whether she could reidentify individuals contained
in the Cancer Registry based upon the Registry information and
anything else she could find from other public sources. The data
fields she was given from the registry were the type of cancer, the
date of the diagnosis and the ZIP code in which the patient
residedBthe identical fields of information requested by plaintiff in its
FOIA request. Dr. Sweeney testified that in conducting this
experiment she used a regular laptop computer, commercially
available spreadsheet software, the information from the Cancer
Registry sought by plaintiff, and any other information that she could
obtain through Internet access. Upon completion of her experiment,
Dr. Sweeney testified, she was able to supply a single correct name
for 18 of 20 sets of data given to her by the Department from the
Cancer Registry. In addition, Dr. Sweeney was able to suggest two
alternative namesBone of which was correctBfor the remaining two
data sets. According to Dr. Sweeney, the information in the Cancer
Registry requested by plaintiffBthe date of diagnosis, patient=s ZIP
code and type of cancerBcould be correctly reidentified in from 80%
to 87% of all instances.



                                  -9-
     Dr. Sweeney then went on to testify at length as to the exact
steps that she took in order to arrive at these identifications. The
circuit court, fearing that Dr. Sweeney=s testimony could serve as an
Ainstruction book@ for anyone attempting to replicate what Dr.
Sweeney had done, sealed that portion of Dr. Sweeney=s testimony in
which she set forth the methodology she used to make these
identifications. We have thoroughly examined Dr. Sweeney=s sealed
testimony for the purposes of this appeal. Without divulging the
specifics of the testimony placed under seal by the circuit court, we
briefly outline, in general terms, the method employed by Dr.
Sweeney in her experiment.
     Dr. Sweeney testified that she used a multistep method to
identify the individuals in the Cancer Registry. She stated that she
began by researching the disease of neuroblastoma to familiarize
herself with its symptoms, diagnosis and treatment. She then
purchased several publicly available data sets, ranging in price from a
few hundred dollars to over a thousand dollars. Dr. Sweeney testified
that her costs associated with this experiment were approximately
$2,000. Dr. Sweeney stated that she used some Asemi-public@ data
sets, which she described as a Aslightly more expensive version@ of
the public data set which contains the same information but in an
easier-to-examine format. Dr. Sweeney testified that, in most
instances, in order to obtain the information she used in her
experiment, she had to fill out forms, wait for her request to be
processed, and received the records in the mail in a CD-format.
     Based upon what she learned through her research on
neuroblastoma, Dr. SweeneyBwith the assistance of a spreadsheet
computer programBthen searched the public data sets for what she
believed would be relevant information leading to the identification
of patients afflicted with this specific disease. Dr. Sweeney
commented that some of the data sets she used consisted of files
which contained Aabout a million records.@ She stated that she
scrutinized the data sets to determine what factors neuroblastoma
cases may have in common. At one point, Dr. Sweeney testified, she
settled on a certain factor. However, when she used that factor as part
of her analysis, she discovered that she had made a mistake, as that
particular factor was far too broad and, accordingly, encompassed far
too many cases other than those of neuroblastoma. Dr. Sweeney then
went back to the data sets and focused on a second factor which she

                                -10-
believed was common to all neuroblastoma cases. This time, Dr.
Sweeney testified, when she ran this particular factor through her
analysis, she had discovered that she had found a far more accurate
match. She then gathered information from other on-line sources, as
well as from libraries and newspaper archives, in order to accurately
arrive at the names of 18 of 20 individuals listed in the Registry.
      Dr. Sweeney stated that she was able to make these
identifications almost solely by use of the information she discovered
in the publicly available data sets. According to Dr. Sweeney, the use
of the data that she received from the Cancer Registry performed two
functions. First, the Cancer Registry information helped to narrow the
fields of the ZIP codes that she used in her search of the public
records. Second, she was able to check the accuracy of her analysis
by using the Registry information to verify that the individuals that
she believed were afflicted with neuroblastoma actually had that
disease.
      When asked whether she could identify neuroblastoma patients
from the publicly available data sets without resorting to the
information in the Cancer Registry, Dr. Sweeney responded, AYes, I
can definitely identify neuroblastoma patients, but would I be
accurate or would I be correct or accurate is a different question ***
.@ In her testimony, Dr. Sweeney characterized the Cancer Registry as
the Agold standard@ that allowed her to match the results she obtained
from the public data sets for accuracy, and also informed her how
good the profile of the neuroblastoma victim that she created was. Dr.
Sweeney stated that although she could identify the neuroblastoma
patients without the information contained in the Cancer Registry,
only relying upon the publicly available data sets, she also stated that
she Acould not do it with that method with confidence, not with this
kind of accuracy.@
      Dr. Sweeney concluded her testimony by stating that, in her
opinion, it is very easy for anyone to identify persons from the
Cancer Registry using public data sets. She explained:
          AIt is very easy in the following sense, all I used was
          commonly available PC technology *** [and] readily
          available software *** and all that was required were the
          simple programs of using [spreadsheets]. *** They come
          almost on every machine now days *** so they don=t require

                                 -11-
         you have any programming or require you to take a
         computer class, but they do require you to know the basics
         of how to use the machine and how to use those simple
         packages.@
Upon the conclusion of Dr. Sweeney=s testimony, the Department
rested its case. Plaintiff presented no witnesses.
     The circuit court, in an oral ruling, delivered its judgment
immediately after the parties concluded closing arguments. The
circuit court focused on the issue as framed by the appellate court:
whether the information sought by plaintiff reasonably tended to lead
to the identity of any person whose condition or treatment is
submitted to the Cancer Registry, thereby violating section 4(d) of
the Registry Act, and in turn, making the information exempt under
section 7(1)(a) of the FOIA. The court answered this question in the
negative, and explained its reasoning as follows:
          AI have to make a determination of what reasonable is, and
         to say that with the three factors that are requested by
         plaintiff, a reasonable person could walk to a computer and
         get thisBuse this information to determine what children in a
         given community have neuroblastoma, I don=t think is
         correct. They don=t have the computer skills. They don=t
         have the knowledge of information databases, I think don=t
         have the knowledge as to how to doBor the analytical skills
         is what I am trying to say. *** [H]ow many people have the
         thousands of dollars and we=ll even say hundreds of dollars
         necessary to secure the databases to get this done? The key
         has to be that the information requested reasonably tends to
         lead to the identity of specific persons. It does not lead in
         this case. It affirms or confirms information which is
         gathered from other databases. *** Taking the [Cancer
         Registry] information in and of itself divorced from this
         other information *** leads nowhere.
             So, it is the finding of the court that the information
         requested will not reasonably tend to lead to the
         identification of individuals. The right of the public to the
         information requested is best met by disclosure due to the
         substantial health risk of the condition for which the
         information is sought. The court orders that the information

                                -12-
          requested be provided and that the plaintiff directly or
          indirectly shall not attempt to locate any individuals who
          may be an individual contained in the statistics released.@
     On June 7, 2002, the circuit court entered a written order of
judgment, memorializing the oral ruling it rendered on the previous
day. In holding that the information requested by plaintiff did not
Areasonably tend to lead to the identity of specific persons,@ the court
provided additional reasoning in support of its result:
          AThe knowledge which Dr. Sweeney acquired during her
          education and in her professional career provided her with a
          foundation upon which she drew in conducting her
          experiments. This knowledge allowed her to know which
          data bases to look for and to cross index. The foundation of
          knowledge acquired by Dr. Sweeney is unique but not
          exclusive. It is not reasonable to believe that someone with
          less knowledge, education and experience in this area would
          be as successful as Dr. Sweeney in using the information to
          arrive at the same result she achieved.
             It was the unique data bases of information which were
          utilized by Dr. Sweeney that provided the identifying
          information rather than the information which was requested
          by the plaintiff. Even without the information requested by
          the plaintiff, Dr. Sweeney testified she would be able to
          identify specific individuals.
             The information requested by the plaintiff does not lead to
          the identification of individuals. The information requested
          may confirm results of analysis of data retrieved from other
          sources. However, the information, in and of itself, does not
          lead to the identification. It is one *** piece of information
          in a melange of data which, when properly analyzed, could
          assist in confirming the identity of individuals. This falls far
          short of >reasonably tending to lead to the identity of
          particular individuals.= @
     On appeal, the appellate court affirmed the circuit court=s
judgment directing the Department to release the data requested by
plaintiff. 349 Ill. App. 3d 431 (Southern Illinoisan II). The appellate
court rejected the Department=s assertion that an individual did not
need to be a professor from MIT to discover the identity of Cancer

                                  -13-
Registry members from the data plaintiff requested in this case.
AAlthough it is true, as the defendants contend, that Dr. Sweeney
testified that she did her work on a simple laptop computer using
standard, readily available software, we do not believe that it was Dr.
Sweeney=s equipment alone or her equipment in conjunction with a
passing knowledge of computing that made it possible for her to
identify the subjects in question. Rather, it was, as the circuit court
noted, her knowledge, education, and experience that allowed her to
make the identifications.@ Southern Illinoisan II, 349 Ill. App. 3d at
434.
      Accordingly, the appellate court found it difficult to believe that
an average person with less knowledge, education and experience
than Dr. Sweeney would have been able to construct and navigate the
multistep methodology used to identify those listed as part of the
Cancer Registry. In addition, the appellate court found that Dr.
Sweeney=s testimony failed to present the court with a reasoned
measure of the threat that might exist from the release of this
information to plaintiff or, for that matter, to the public in general.
The appellate court explained:
         A[W]hile the evidence presented by the defendants
         demonstrates that one expert in data anonymity was able to
         identify the subjects in question from the data requested by
         the plaintiff, following her own six-step process and drawing
         upon her years of education, knowledge, and experience to
         analyze the data to the extent necessary to identify the
         subjects in question, that evidence does not concretely and
         conclusively demonstrate that a threat exists that other
         individuals, even those with skills approaching those of Dr.
         Sweeney, likewise would be able to identify the subjects or
         what the magnitude of such a threat would be, if it existed.
         Are there two people in the entire State of Illinois who could
         replicate Dr. Sweeney=s results with the same limited data or
         are there two thousand? Are there zero or are there a
         million? These questions are significant because without
         some sense of the magnitude of the alleged threat of which
         the defendants complain, it is very difficult for this court to
         determine whether the data in question reasonably tends to
         lead to the identity of specific persons.@ Southern Illinoisan
         II, 349 Ill. App. 3d at 435.

                                 -14-
     The appellate court noted that, in its prior opinion in Southern
Illinoisan I, it held that it is necessary to impose a Areasonableness@
requirement in assessing whether the information requested by
plaintiff from the Cancer Registry consists of a Agroup of facts that
tends to lead to the identity@ of those listed in the Registry. Applying
that rule to the facts presented, the appellate court held that the
Department did not meet this burden. The appellate court explained:
          A[T]he fact that one expert in data anonymity can manipulate
          data to determine identity does not necessarily mean,
          without more, that a threat exists that other individuals will
          be able to do so as well, nor does it in any way define the
          magnitude of such a threat or whether that threat, if it in fact
          even exists, renders the release of the data an act that
          reasonably tends to lead to the identity of specific persons.
          To find otherwise would undermine the reasonableness
          requirement and would effectively remove it from our
          analysis, leading to a situation where if it could be shown
          that one expert could identify individuals from information
          released, then the release of that information would
          automatically be deemed to reasonably tend to lead to the
          identity of specific persons.@ Southern Illinoisan II, 349 Ill.
          App. 3d at 436.
     This court granted the Department=s petition for leave to appeal
pursuant to our Rule 315 (177 Ill. 2d R. 315). We also granted leave
to the Associated Press, the Copley Press, Inc., Gannett Company,
Inc., the Illinois Press Association and the Tribune Company to file
an amicus curiae brief in support of plaintiff.

                              ANALYSIS
     This appeal presents the sole question of whether the information
requested from the Department by plaintiff pursuant to the FOIA
Atends to lead to the identity@ of patients listed in the Cancer Registry,
thereby violating section 4(d) of the Registry Act (410 ILCS 525/4(d)
(West 1998)). If so, then the information requested by plaintiff is
exempt from disclosure under section 7(1)(a) of the FOIA (5 ILCS
140/7(1)(a) (West 1998)).
     The Department contends that the appellate court erred in
affirming the circuit court=s order that the Department disclose the

                                  -15-
Cancer Registry information requested by plaintiff. The Department
begins its argument by observing that when a citizen of this state is
diagnosed with cancer, that fact is mandatorily reported to the
Department and the patient=s information is recorded in the Cancer
Registry. The Department notes that the collection of such health
information implicates the privacy concerns of the patients whose
information is contained within the Registry. The Department asserts
that the subsequent dissemination of the collected health information
multiplies the potential privacy loss, especially if that dissemination
is to a newspaper, such as plaintiff. Accordingly, the Department
maintains, the legislature sought to restrict the dissemination of the
patient information contained within the Cancer Registry. To this
end, the Department asserts, the legislature prohibited within section
4(d) of the Registry Act the disclosure not only of the identity of the
patient, but also of any information or group of information that even
Atends to lead@ to the identity of any person whose condition or
treatment is submitted to the Registry.
      The Department contends that the lower courts applied an
incorrect legal standard in this case, one that is at odds with the
standard established by the General Assembly. According to the
Department, the lower courts departed from the well-settled rule that
in construing a statute, the plain language of the enactment must be
used. The Department maintains that the appellate court erred in
reasoning that all information in some remote fashion would Atend to
lead to the identity@ of cancer patients, and therefore incorrectly
advised the circuit court to determine whether the release of the
information would reasonably tend to lead to the identity of specific
persons. Although the Department acknowledges in its brief to this
court that the word Atends@ is Aadmittedly not very precise and
potentially might be interpreted too broadly,@ the Department also
takes the position that the legislature used the word Atends@ to
indicate a broader prohibition than just information that simply Aleads
to the identity@ of cancer patients. According to the Department, the
appellate court=s addition of the word Areasonably@ to the Atends to
lead to the identity@ standard does not improve the analysis. The
Department asserts that the word Areasonably@ has the same imprecise
quality as the word Atends,@ and it can be Ainterpreted so broadly that
it nullifies the word >tends= and thwarts the legislative purpose in
using that word.@

                                -16-
     The Department also argues that the uncontested evidence
presented in the cause before us demonstrates that the Cancer
Registry information requested by plaintiff tends to lead to the
identity of cancer patients. The evidence includes Dr. Sweeney=s
unrebutted assertion that 80% to 87% of the individuals in the Cancer
Registry could be uniquely and correctly identified if the Department
released the data requested by plaintiff. The record also includes Dr.
Sweeney=s expert opinion that a number of individuals in the general
public with access to a personal computer, using traditional database
software, who purchase or acquire public data sets, will be able to
identify individuals listed in the Cancer Registry. Thus, the
Department argues, the record establishes that the three data elements
requested by plaintiffBthe patient=s type of cancer, the date of
diagnosis and the patient=s ZIP codeBtend to lead to the identity of
cancer patients and therefore violates section 4(d) of the Registry
Act.
     In addition, the Department asserts that the appellate court in
Southern Illinoisan II Asignificantly exaggerate[d] [the] complexity@
of Dr. Sweeney=s experiment. The Department also states that even
though Dr. Sweeney testified that the Cancer Registry information
only assisted her in confirming the identity of the individuals, this
testimony is sufficient to establish that the information requested by
plaintiff under the FOIA Atends to lead@ to the identities of the
patients listed in the Registry.
     With respect to the appellate court=s prior decision in May, the
Department asserts that Dr. Sweeney=s testimony is a crucial
distinguishing factor between that case and the instant matter. The
Department asserts that the May court=s observation that it could not
see how dissemination of a person=s ZIP code, type of cancer and date
of diagnosis could tend to lead to the patient=s identity describes a
situation that is directly contrary to the factual evidence presented in
the instant case as a result of Dr. Sweeney=s testimony.
     Finally, the Department also criticizes the lower courts for
stressing only one of the purposes of the Cancer RegistryBto provide
information to the publicBand connecting that purpose to the release
of raw public data. The Department asserts that the courts overlooked
that the Registry Act has not one, but several, goals, and that



                                 -17-
releasing raw data is neither the onlyBnor the bestBway to achieve the
Act=s purposes.
     For all of the above reasons, the Department concludes that the
information requested by plaintiff from the Cancer Registry tends to
lead to the identity of cancer patients included in the Registry.
Accordingly, the Department asserts, the information is prohibited
from disclosure under section 4(d) of the Registry Act and, therefore,
exempt from disclosure under section 7(1)(a) of the FOIA (5 ILCS
140/7(1)(a) (West 1998)).
     In response, plaintiff asserts that the appellate court correctly
affirmed the judgment of the circuit court requiring the Department to
comply with plaintiff=s FOIA request. Plaintiff contends that the
FOIA is to be interpreted in favor of disclosure and that the
exemptions from disclosure are to be read narrowly. In addition,
plaintiff asserts, the public policy concerns which underpin the
Registry ActBmost specifically that the Registry information be used
to alert citizens about risks, early detection and treatment of cancers
known to be elevated in their communitiesBfavor disclosure of the
information requested by plaintiff. Although plaintiff acknowledges
that the Registry Act has an Ainherent tension@ between patient
privacy and a community=s right to know about elevated levels of
cancer in its geographic area, plaintiff argues that the balance is
tipped by the fact that the FOIA is to be given a liberal interpretation
and that the exceptions to disclosure are narrow.
     In addition, plaintiff contends, the lower courts correctly ruled
that the Department did not meet its burden of proof in this case.
Plaintiff emphasizes that under the FOIA, the Department bears the
burden of proof to establish that an exemption from disclosure
applies. According to plaintiff, a review of the record reveals that at
no point did the Department demonstrate that release of the requested
information would tend to lead to the identity of any person whose
condition or treatment was submitted to the Cancer Registry.
     With respect to Dr. Sweeney=s experiment, plaintiff stresses that
Dr. Sweeney is an expert at adeptly working with all types of data,
and that she possesses knowledge through her education and career
which allowed her to easily perform the experiment. Plaintiff asserts
that, based upon Dr. Sweeney=s testimony, it was apparent that she
knew which data sets to use, how and where to obtain these data sets,

                                 -18-
and the most efficient manner in which to review the applicable
records. Plaintiff also stresses that Dr. Sweeney testified that she used
public data setsBand not the Cancer Registry informationBto identify
individual patients. Plaintiff notes that Dr. Sweeney testified that she
used the Cancer Registry information only to verify her work. In its
brief to this court, plaintiff asserts that A[i]f this court adopts the
privacy position asserted by the Department (that privacy is invaded
by the release of data by diagnosis, date of diagnosis and zip code)
then it would be impossible to meet the other goals of [the Registry]
Act,@ meaning that it will be impossible to inform health
professionals and citizens of risks of cancer known to be elevated in
their communities.
      Plaintiff concludes its argument by noting that in May, the
appellate court had occasion to examine section 4 of the Registry Act
in relation to the release of Cancer Registry neuroblastoma
information identical to that requested in this case. In May, the
appellate court held that the disclosure of the information was not
prohibited. Plaintiff urges a similar outcome here. Plaintiff also notes
that if disclosure of the information is ordered, it has agreed to be
bound by the circuit court=s order that it would not use the Cancer
Registry information in any way to identify the individuals. In
conclusion, plaintiff urges this court to affirm the rulings of the lower
courts directing the Department to comply with plaintiff=s FOIA
request.
      In support of the position taken by plaintiff in the instant cause,
the Associated Press, the Copley Press, Inc., Gannett Company, Inc.,
the Illinois Press Association and the Tribune Company have filed a
brief with this court as amici curiae. According to the amici news
organizations, because they Adepend on FOIA to open government
files to public scrutiny, they have a keen interest in both the outcome
of this case and its impact on the future of FOIA.@ The amici argue
that both the language and purpose of the FOIA instruct that public
records cannot be withheld unless the government meets its burden of
proving, by a preponderance of the evidence, that an invasion of
privacy will occur if the records are released. The amici emphasize
that plaintiff is not seeking to expose private information about
specific individuals. Rather, plaintiff has requested Amasked@ data
that may shed light on possible links between hazardous substances
and cancer, an issue of great public interest and one that the

                                 -19-
legislature specifically contemplated in requiring the data collection
under the Registry Act. The amici assert that if the data were to show
that an unusual type of cancer occurred in an extraordinary number of
cases in one particular ZIP code, surely that would be of concern to
everyone in that ZIP codeBand to people in other areas as well. The
amici argue that the lower courts correctly decided that plaintiff=s
FOIA request should be granted, and that the requested information
does not tend to lead to the identity of any patients listed in the
Cancer Registry.
     In the instant appeal, our inquiry is whether the circuit court
properly granted plaintiff=s FOIA request for disclosure of Cancer
Registry information relating to incidences of neuroblastoma by type
of cancer, the date of diagnosis and the patient=s ZIP code. We reject
the arguments advanced by the Department, and agree with plaintiff
that the lower courts correctly required disclosure of the requested
information. Our analysis begins by examining the relationship
between the FOIA and the Registry Act.
     Our review of the FOIA and the Registry Act is guided by
several well-established principles of statutory construction. It is well
settled that the primary objective of this court when construing the
meaning of a statute is to ascertain and give effect to the intent of the
General Assembly. People ex rel. Sherman v. Cryns, 203 Ill. 2d 264,
279 (2003). In determining legislative intent, our inquiry begins with
the plain language of the statute, which is the most reliable indication
of the legislature=s objectives in enacting a particular law. In re
Madison H., 215 Ill. 2d 364, 372 (2005). A fundamental principle of
statutory construction is to view all provisions of a statutory
enactment as a whole. Accordingly, words and phrases should not be
construed in isolation, but must be interpreted in light of other
relevant provisions of the statute. Michigan Avenue National Bank v.
County of Cook, 191 Ill. 2d 493, 504 (2000). In construing a statute,
we presume that the legislature, in its enactment of legislation, did
not intend absurdity, inconvenience or injustice. Burger v. Lutheran
General Hospital, 198 Ill. 2d 21, 40 (2001).
     The Apurpose of the FOIA is to open governmental records to the
light of public scrutiny.@ Bowie v. Evanston Community Consolidated
School District No. 65, 128 Ill. 2d 373, 378 (1989). Accordingly,
under the FOIA, Apublic records are presumed to be open and


                                 -20-
accessible.@ Lieber v. Board of Trustees of Southern Illinois
University, 176 Ill. 2d 401, 407 (1997); see also Illinois Education
Ass=n v. Illinois State Board of Education, 204 Ill. 2d 456, 462-63
(2003). This legislative intent is set forth by the General Assembly in
section 1 of the FOIA:
             APursuant to the fundamental philosophy of the American
         constitutional form of government, it is declared to be the
         public policy of the State of Illinois that all persons are
         entitled to full and complete information regarding the
         affairs of government and the official acts and policies of
         those who represent them as public officials and public
         employees consistent with the terms of this Act. Such access
         is necessary to enable the people to fulfill their duties of
         discussing public issues fully and freely, making informed
         political judgments, and monitoring government to ensure
         that it is being conducted in the public interest.
             This Act is not intended to be used to violate individual
         privacy, *** or to disrupt the duly-undertaken work of any
         public body independent of the fulfillment of any of the
         forementioned rights of the people to access to information.
             ***
             These restraints on information access should be seen as
         limited exceptions to the general rule that the people have a
         right to know the decisions, policies, procedures, rules,
         standards, and other aspects of government activity that
         affect the conduct of government and the lives of any or all
         of the people. The provisions of this Act shall be construed
         to this end.@ 5 ILCS 140/1 (West 1998).
     Based upon the legislature=s clear expression of public policy
and intent set forth in section 1 of the FOIA that the purpose of that
Act is to provide the public with easy access to government
information, this court has held that the FOIA is to be accorded
Aliberal construction to achieve this goal.@ Bowie, 128 Ill. 2d at 378.
Accordingly, we have, on several occasions, held that the exceptions
to disclosure set forth in the FOIA are to be read narrowly so as not
to defeat the FOIA=s intended purpose. See, e.g., Illinois Education
Ass=n, 204 Ill. 2d at 463; Lieber, 176 Ill. 2d at 407; American
Federation of State, County & Municipal Employees (AFSCME) v.

                                -21-
County of Cook, 136 Ill. 2d 334, 341 (1990). Therefore, Awhen a
public body receives a proper request for information, it must comply
with that request unless one of the narrow statutory exemptions set
forth in section 7 of the Act applies.@ Illinois Education Ass=n, 204 Ill.
2d at 463; Lieber, 176 Ill. 2d at 408; AFSCME, 136 Ill. 2d at 341; 5
ILCS 140/3(a) (West 1998) (AEach public body shall make available
to any person for inspection or copying all public records, except as
otherwise provided in Section 7 of this Act@).
     Section 7 of the FOIA (5 ILCS 140/7 (West 1998)) sets forth a
number of exemptions from disclosure, most of which are specific
and identify the particular records that are shielded from disclosure.
In the instant cause, the Department relies upon the exemption set
forth in section 7(1)(a), which provides:
            A(1) The following shall be exempt from inspection and
          copying:
               (a) Information specifically prohibited from disclosure
            by federal or State law or rules and regulations adopted
            under federal or State law.@ 5 ILCS 140/7(1)(a) (West
            1998)).
     This court has held that A>[i]f the public body seeks to invoke one
of the exemptions in section 7 as grounds for refusing disclosure, it is
required to give written notice specifying the particular exemption
claimed to authorize the denial.= @ Illinois Education Ass=n, 204 Ill. 2d
at 464, quoting Lieber, 176 Ill. 2d at 408; 5 ILCS 140/9(b) (West
1998). Any person denied his or her request for disclosure under the
FOIA may appeal the denial by sending a written notice of appeal to
the head of the public body. An individual has exhausted his or her
administrative remedies with respect to the FOIA request if the head
of the public body affirms the denial or fails to act within specified
time limits. 5 ILCS 140/10 (West 1998).
     Thereafter, the party seeking disclosure of the requested
information may challenge the denial in the circuit court. 5 ILCS
140/11(a) (West 1998). Section 11(f) of the FOIA (5 ILCS 140/11(f)
(West 1998)) sets forth the procedures to be followed by the circuit
court in reviewing a denial of a FOIA request. This section provides
that the court shall conduct the hearing Ade novo@ and shall conduct
such in camera examination of the requested records as it finds
appropriate to determine if such records or any part thereof may be

                                  -22-
withheld under any provision of the FOIA (5 ILCS 140/11(f) (West
1998)). The burden shall be on the public body to establish that its
refusal to permit public inspection or copying is in accordance with
the provisions of the FOIA and that the records fall within the
exemption it has claimed. 5 ILCS 140/11(f) (West 1998); see also
Illinois Education Ass=n, 204 Ill. 2d at 464; Lieber, 176 Ill. 2d at 407-
08.
      Applying this statutory framework to the matter before us, the
Department bears the burden of establishing that the Cancer Registry
records requested by plaintiff fall within the exemption contained in
section 7(1)(a) of the FOIA: that the information is Aspecifically
prohibited from disclosure by *** State law.@ 5 ILCS 140/7(1)(a)
(West 1998). The Department asserts that the disclosure of the
requested information violates section 4(d) of the Registry Act
because it Atends to lead to the identity, of any person whose
condition or treatment is submitted to the Illinois Health and
Hazardous Substances Registry.@ 410 ILCS 525/4(d) (West 1998).
Accordingly, we turn to an examination of the Registry Act.
      In section 2 of the Registry Act, the General Assembly set forth
its legislative findings. The General Assembly stated that a serious
threat to public health and welfare is posed by hazardous substances,
and thatBprior to the enactment of this legislationBthere existed no
coordinated effort to collect and analyze information with respect to
hazardous substances and their potential health effects. 410 ILCS
525/2(a)(i), (a)(ii) (West 1998). In addition, the legislature
acknowledged that this Alack of comprehensive information has
caused concern on the part of Illinois citizens and a lack of effective
control by the State government.@ 410 ILCS 525/2(a)(iii) (West
1998).
      In response to these concerns, the General Assembly enacted the
Registry Act, because Ait is the obligation of the State government to
inform and protect the citizens of Illinois by developing a
comprehensive and integrated data system on hazardous substances
and public health.@ 410 ILCS 525/2(a)(iv) (West 1998). In sections
2(b) and (c), the legislature enumerated the purposes of the Registry
Act:
             A(b) It is the purpose of this Act to establish a unified
          Statewide project to collect, compile and correlate

                                 -23-
          information on public health and hazardous substances. Such
          information is to be used to assist in the determination of
          public policy and to provide a source of information for the
          public, except when public disclosure of the information
          would violate the provisions of subsection (d) of Section 4
          concerning confidentiality.
             (c) In particular, the purpose of the collection of cancer
          incidence information is to:
             (1) monitor incidence trends of cancer to detect potential
          public health problems, predict risks and assist in
          investigating cancer clusters;
             (2) more accurately target intervention resources for
          communities and patients and their families;
             (3) inform health professionals and citizens about risks,
          early detection and treatment of cancers known to be
          elevated in their communities; and
             (4) promote high quality research to provide better
          information for cancer control and to address public
          concerns and questions about cancer.@ 410 ILCS 525/2(b),
          (c) (West 1998).
     Although it is apparent from the above-quoted sections of the
Registry Act that the legislature intended the FOIA to facilitate public
access to information with respect to hazardous substances and
increased incidences of cancer, it is also apparent from section 4(d) of
the Registry Act that, in certain instances, the General Assembly
intended to limit public access to information in order to protect the
privacy of cancer patients included in the Registry. At the time
plaintiff made its FOIA request to the Department, section 4(d) of the
Registry Act provided in pertinent part:
             AThe identity, or any group of facts that tends to lead to
          the identity, of any person whose condition or treatment is
          submitted to the Illinois Health and Hazardous Substances
          Registry is confidential and shall not be open to public
          inspection or dissemination.@ 410 ILCS 525/4(d) (West
          1998).
Subsequently, the legislature amended section 4(d) to include a new
sentence immediately following the portion quoted above:


                                 -24-
         AFacts that tend to lead to the identity of a person include the
         following: name, social security number, address, and any
         other data element that, by itself or in combination with one
         or more other data elements, tends to identify any person.@
         410 ILCS 525/4(d) (West 1998) (as amended by Pub. Act
         90B607, '20, eff. June 30, 1998).
The confidentiality requirements of the Registry Act are further
underscored in section 4(e) of the Act, which mandates that A[t]he
Department shall protect any information made confidential or
privileged under law.@ 410 ILCS 525/4(e) (West 1998). Section 12 of
the Registry Act similarly provides that
            AAll information contained in the Registry *** shall be
         made available to the public upon request; provided,
         however, nothing in this Act permits public disclosure of any
         information made confidential or privileged pursuant to this
         Act or any other statute.@ 410 ILCS 525/12 (West 1998).
     Thus, a review of the pertinent statutory provisions underscores
that the competing interests in this case are the interest in providing
public access to meaningful information about potential Acancer
clusters@ and the interest in minimizing the risk of invading the
privacy of cancer patients. Indeed, these competing interests are
captured in section 4(d) of the Registry Act, which prohibits the
disclosure of otherwise publicly available information if it Atends to
lead to the identity@ of the cancer patients listed in the Registry.
     We find that under either the original version of section 4(d) of
the Registry ActBwhich applies in this case, as it was the statute in
effect at the time of the occurrenceBor the subsequently amended
version of section 4(d), which sets forth a nonexclusive list of A[f]acts
that tend to lead to the identity of a person,@ the relevant inquiry
remains the same. We must determine the meaning of the phrase
Atends to lead to the identity@ as it is used in section 4(d) of the
Registry Act. Because this is an issue of statutory interpretation, our
review is de novo. In re Estate of Dierkes, 191 Ill. 2d 326, 330
(2000).
      In general, Atend@ has been defined as meaning A[t]o be disposed
toward (something),@ to Aserve, contribute or conduce in some degree
or way,@ and A[t]o be directed or have a tendency to (an end, object,
or purpose).@ Black=s Law Dictionary 1479 (7th ed. 1999). In the

                                 -25-
specific context of the Registry Act, we believe that the General
Assembly selected to employ the word Atends@ in the phrase Atends to
lead to the identity@ because it is a term that is fluid and allows a
case-by-case determination of whether the information at issue is
subject to disclosure. We agree with the Department that the word
Atends@ is Anot very precise.@ We observe, however, that by
employing the word Atends,@ the legislature deliberately allowed for
flexibility, to the extent that, in some instances, disclosure of Registry
information will be permissible and in other instances such disclosure
will be prohibited. As stated above, there are competing interestsBand
therefore an inherent tensionBwithin the Registry Act: the purpose of
the Act is to provide the public with information about hazardous
substances and cancer, while at the same time the Act is intended to
protect the identity of those patients afflicted with this disease. The
use of the term Atends@ indicates that the General Assembly wished to
impose a somewhat heightened standard of confidentiality by
prohibiting disclosure of Registry information other than just
information that simply Aleads to the identity@ of cancer patients.
However, at the same time, the use of the word Atends@ also indicates
that the legislature did not intend to erect a per se bar to the
disclosure of Registry information, and we must, therefore, be
mindful not to interpret this term too broadly. In our view, by
choosing to use the word Atends,@ the legislature has allowed for case-
specific determinations with the respect to the release of Cancer
Registry information, with the analysis meant to be adaptable to the
particular circumstances presented.
     However, we disagree with the appellate court below that, in
order to preserve the intent of the legislature, the word Areasonably@
must be inserted immediately before the phrase Atends to lead to the
identity@ in section 4(d) of the Registry Act. We agree with the
Department to the extent that it is neither appropriate nor necessary to
insert the word Areasonably@ into section 4(d). It is apparent from the
appellate court=s opinions in Southern Illinoisan I and II that the
addition of the word Areasonably@ by the appellate court below was
driven by that court=s concern that an extreme hypothetical situation
could occur in which disclosure of any fact, no matter how unrelated
to an individuals= identity, could Atend@ to lead to identity of an
individual listed in the Registry. In turn, the appellate court feared,
any and every fact would therefore be exempt from disclosure under

                                  -26-
section 4(d). Southern Illinoisan I, 319 Ill. App. 3d at 987; see also
Southern Illinoisan II, 349 Ill. App. 3d at 432. In other words, the
court surmised that the word Atends@ could lead to a per se exemption
from disclosure in each and every instance. However, as stated, we
do not believe that this was the intent of the legislature; rather, the
intent, as we discern it, was to craft a flexible standard that would
allow thoughtful consideration of each case upon its own unique
facts. Accordingly, it is our belief that the purposes of the Registry
Act can be achieved using its plain language without inserting
additional language into section 4(d).
     In the matter before us, the Department relies upon the testimony
of Dr. Sweeney to support its position that the information requested
by plaintiff is prohibited from disclosure pursuant to section 4(d) of
the Registry Act because it consists of a Agroup of facts that tends to
lead to the identity@ of patients listed in the Cancer Registry.
However, we find that it is not entirely clear from section 4(d) of the
Registry Act whether the legislature intended that disclosure of the
Registry information is prohibited upon a showing by the Department
that the challenged information Atends to lead to the identity@ of
Registry patients based upon experiments conducted by experts, such
as Dr. Sweeney, or if disclosure is prohibited upon a showing that the
general public at large is capable of making such identifications. In
other words, how revealing must the challenged information be, and
to whom? Is the standard that an expert with knowledge and money
can identify the Registry patients? Or is it that the general public,
who may not have the same knowledge or funds, can make the
identification? In addition, how much money, effort, time, and
expertise must be expended? Given this uncertainty in interpretation,
we are especially mindful of the public policy which underpins both
the Registry Act and the FOIA: to ensure public disclosure of
government information that is not otherwise protected. We also note,
as stated above, that under the FOIA, public records are presumed to
be open and accessible, with exceptions to disclosure to be read
narrowly. Accordingly, in light of these public policies, we conclude
that information Atends to lead to the identity@ of Registry patients
only if that information can be used by the general public to make
those identifications.
     In the instant matter, the DepartmentBthrough the testimony of
Dr. SweeneyBestablished that an expert with years of experience,

                                -27-
specific knowledge of data systems, and the ability to adeptly
manipulate data could identify patients listed in the Cancer Registry
by using the information requested by plaintiff as one part of her
multistep experiment. We note, however, that the Department failed
to establish that individual members of the general public could
recreate what was accomplished by Dr. Sweeney. Through Dr.
Sweeney=s testimony, the Department showed that a dedicated
computer professional, with knowledge of unfamiliar data sets, and
with $2,000 in funds to obtain the data, could identify the patients
listed in the Cancer Registry. However, at trial, the Department did
not adduce competent evidence of whether a nonexpert could perform
the multistep procedure performed by Dr. Sweeney to identify Cancer
Registry patients.
      We note that the Department places great emphasis upon that
portion of Dr. Sweeney=s testimony wherein she stated her opinion
that the general public could identify the patients listed in the Cancer
Registry. Yet, other than Dr. Sweeney=s mere conclusion, the
Department adduced no proof on this point. After carefully reviewing
the testimony of Dr. Sweeney, the circuit court concluded that it was
her Aknowledge, education and experience in this area@ that made it
possible for her to identify the Registry patients. This factual finding
is not against the manifest weight of the evidence. The methodology
Dr. Sweeney used to conduct her experiment was not as simple as
sheBor the DepartmentBhas stated. We disagree with the
Department=s assertion in its brief to this court that the appellate court
in Southern Illinoisan II Asignificantly exaggerate[d] [the]
complexity@ of Dr. Sweeney=s experiment.@ Our thorough
examination of the record leads us to the conclusion that although Dr.
Sweeney stated that the equipment and data sets that she used during
her experiment would be readily available to the general public, the
methodology she used during her experiment was unique to her
education, training and experience, and not easily duplicated by the
general public. We agree with the appellate court=s assessment of Dr.
Sweeney=s testimony and, therefore, quote with some length from its
opinion in Southern Illinoisan II:
             ADr. Sweeney testified that she used a six-step method to
          identify the subjects in question. Without divulging
          information under seal, we note that this six-step method
          required knowledge that statistical information of the kind

                                  -28-
she sought existed, skill in the gathering of that information,
the integration and manipulation of the information from
multiple sources so that a coherent picture of the relevance
of each piece of information could be formed, the analysis of
the information to determine its significance to the process
of identification, and the solution of the sometimes complex
problems that developed during the gathering, integration
and manipulation, and analysis stages. The defendants=
assertions to the contrary notwithstanding, the identification
process was not a simple task that almost anyone with a
computer could accomplish. The process required not only
the knowledge that relevant statistical data existed and the
knowledge of where to look for that data but also the
knowledge, education, experience, and skill to know what to
do with that data once it was locatedBto put it all together so
that it made sense. For example, Dr. Sweeney testified that
at one stage in her process she examined six cases to
determine what each case had in common with the others.
Initially, she settled on one factor, but when she sought
medical records on the basis of that factor, she got a huge
number of records back and recognized that the factor in
question was far too broad to help her. That Dr. Sweeney
recognized that she had made a mistake, what the mistake
was, and how to correct the mistake is indicative of her level
of sophistication in this field of study. We find it difficult to
believe that an individual with less knowledge, education,
and experience than Dr. Sweeney has would have been able
to navigate the six-step process as adeptly as she did.
Clearly, Dr. Sweeney=s methodology required knowledge
and analytical skills beyond that of the average person. The
circuit court even engaged Dr. Sweeney in an extended
discussion of her methodology. The trial judge stated, >I
want to go through the project with you step by step as if I
was a computer literate person attempting to recreate what
you did.= Significantly, although Dr. Sweeney=s responses to
this line of questioning by the court indicate in great detail
how she knew what to do, her responses lack concreteness
and specificity regarding the extent to which others would be


                         -29-
          able to do the same. Nor did the defendants present any other
          evidence on this point.
                                   ***
              Had the defendants, with the many and varied resources
          available to a state agency, wished to present specific
          evidence on the extent to which other individuals possess the
          unique knowledge, experience, and analytical skills
          necessary to replicate Dr. Sweeney=s work, they were free to
          do so. Had they chosen to bring in other witnesses who also
          had been able to identify the subjects from the data in
          question, they were free to do that as well. Had they done
          one or both of these things, this court would be in a better
          position to evaluate the threat of which the defendants
          complain. However, the defendants did not do so, and they
          now must stand by the evidence they actually presented, not
          by alarmist conjecture about the resounding policy
          implications of that somewhat limited evidence.@ Southern
          Illinoisan II, 349 Ill. App. 3d at 435-36.
      In sum, we conclude, as did the lower courts in this matter, that
the Department failed to demonstrate that the release of the Cancer
Registry information requested by plaintiff tends to lead to the
identity of the specific persons described in that data. As we have
noted, it was the Department=s burden under the FOIA to establish
that its refusal to release the requested material to plaintiff fell within
the exemption set forth in section 7(1)(a) of the FOIA, by
establishing that the information was prohibited from disclosure
pursuant to section 4(d) of the Registration Act. In the absence of
more definitive proof that individuals of the general public would
have the ability to duplicate Dr. Sweeney=s multistep experiment, our
decision is guided by the public policy of this state, which
Aencourages a free flow and disclosure of information between
government and the people.@ Bowie, 128 Ill. 2d at 378. As the FOIA
is to be interpreted liberally, and the exemptions to disclosure are to
be interpreted narrowly, we conclude that the lower courts properly
instructed the Department to disclose to plaintiff the information
contained in its FOIA request.
      As a final matter, we note that in granting plaintiff access to the
requested information from the Cancer Registry, the circuit court

                                  -30-
ordered plaintiff not to identify those on the Cancer Registry list. We
believe that the court=s order expressly forbidding plaintiff to use the
information in an improper manner will ensure its confidentiality.




                          CONCLUSION
     For the foregoing reasons, the judgment of the appellate court is
affirmed.

                                                             Affirmed.




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