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             DISTRICT OF COLUMBIA COURT OF APPEALS

                                No. 12-CV-351

 FRATERNAL ORDER OF POLICE, METROPOLITAN LABOR COMMITTEE, APPELLANT,

                                       v.

                       DISTRICT OF COLUMBIA, APPELLEE.

                         Appeal from the Superior Court
                          of the District of Columbia
                                (CAB-5152-10)

                    (Hon. John Ramsey Johnson, Trial Judge)

(Argued June 4, 2013                                   Decided January 2, 2014)

      Paul A. Fenn, with whom Erinn M. Maguire was on the brief, for appellant.

       Mary L. Wilson, Senior Assistant Attorney General, Office of the Solicitor
General, with whom Irvin B. Nathan, Attorney General for the District of
Columbia, Todd S. Kim, Solicitor General, and Donna M. Murasky, Deputy
Solicitor General, were on the brief, for appellee.

      Before GLICKMAN and MCLEESE, Associate Judges, and REID, Senior Judge.

      REID, Senior Judge: This appeal arises out of a Freedom of Information Act

(“FOIA”) request made by appellant, the Fraternal Order of Police, Metropolitan

Police Labor Committee (“FOP”), for certain documents related to the “Intoxilyzer

5000EN,” a device used by the Metropolitan Police Department (“MPD”) to
                                          2

measure the amount of alcohol in a suspect’s breath. Appellee, the District of

Columbia, initially denied the request on the basis of the FOIA exemption for

“investigatory records compiled for law enforcement purposes,” set forth in D.C.

Code § 2-534 (2010 Supp.);1 the District’s investigation related to errors in the


      1
          The investigatory records exemption is found in D.C. Code § 2-534 (a)(3):


                (a) The following matters may be exempt from
              disclosure under the provisions of this subchapter: . . .

                 (3) Investigatory records compiled for law-
              enforcement purposes, including the records of Council
              investigations and investigations conducted by the Office
              of Police Complaints, but only to the extent that the
              production       of       such       records      would:

                   (A) Interfere with:
                      (i) Enforcement proceedings;
                      (ii) Council investigations; or
                      (iii) Office of Police Complaints ongoing
              investigations;
                     (B) Deprive a person of a right to a fair trial or an
              impartial adjudication;
                     (C) Constitute an unwarranted invasion of personal
              privacy;
                     (D) Disclose the identity of a confidential source
              and, in the case of a record compiled by a law-
              enforcement authority in the course of a criminal
              investigation, or by an agency conducting a lawful
              national security intelligence investigation, confidential
              information furnished only by the confidential source;
                     (E) Disclose     investigative   techniques      and
              procedures not generally known outside the government;
              or
                                                                         (continued…)
                                         3

Intoxilyzer measurements that resulted in reversals of some convictions for driving

while under the influence. In response to the denial of its FOIA request, FOP filed

a complaint in the Superior Court against the District, alleging FOIA violations and

seeking declaratory and injunctive relief, as well as attorneys’ fees and costs.

Following the completion of its investigation and during the litigation proceedings,

the District produced numerous documents and denied the request for others on

grounds of privilege (attorney-client, deliberative process, and work product).2


(…continued)
                  (F) Endanger the life or physical safety of law-
            enforcement personnel. . . .
      2
        The provisions pertaining to the deliberative process, attorney-client and
work product privileges are contained in D.C. Code § 2-534 (a)(4) and § 2-534 (e):

                   (4) Inter-agency or intra-agency memorandums or
            letters, including memorandums or letters generated or
            received by the staff or members of the Council, which
            would not be available by law to a party other than a
            public body in litigation with the public body . . .

              (e) All exemptions available under this section shall
            apply to the Council as well as agencies of the District
            government. The deliberative process privilege, the
            attorney work-product privilege, and the attorney-client
            privilege are incorporated under the inter-agency
            memoranda exemption listed in subsection (a)(4) of this
            section, and these privileges, among other privileges that
            may be found by the court, shall extend to any public
            body     that    is   subject    to   this    subchapter.
                                           4

Despite numerous issues presented in the trial court by the parties, the court

narrowed the issue to the District’s initial denial of FOP’s document request. FOP

appeals the trial court’s rejection of its challenge to the District’s initial denial of

its request under the investigatory records exemption; and in response to the

District’s argument that the case is moot, FOP continues to preserve its trial court

argument regarding the adequacy of the District’s subsequent FOIA disclosures.



      First, we hold that the case is not moot because the trial court has not

determined whether the District sustained its FOIA burden by disclosing all of the

requested documents to which FOP is entitled. Second, we conclude that FOP has

not forfeited its challenge to the adequacy of the disclosures that the District made

subsequent to its initial response to FOP. Third, we hold that the trial court erred

by granting the District’s motion for summary judgment. Accordingly, for the

reasons stated below, we vacate the trial court’s order and remand this case for

further proceedings consistent with this opinion.



                              FACTUAL SUMMARY



      Relevant background for this appeal reveals that in addition to this FOIA

case concerning MPD’s use of the Intoxilyzer 5000EN to determine whether
                                          5

persons who had been stopped by police officers were driving while under the

influence of or impaired by alcohol, civil cases pertaining to allegedly erroneous

breathalyzer readings were proceeding through the federal district court for the

District of Columbia. At various times during the first half of the year 2010,

approximately twenty persons sued the District of Columbia and MPD Officer

Kelvin King in federal district court, alleging constitutional violations due to their

convictions for driving while intoxicated (“DWI”).              Those cases were

consolidated. See Molina-Aviles v. District of Columbia, 824 F. Supp. 2d 4, 5 n.1

(D.D.C. 2011).



      The consolidated federal case showed that Officer King, head of MPD’s

Impaired Driver Support Unit, was “responsible for calibrating the breath test

machines and testing them for accuracy.” Id. at 6. He had been assigned that

responsibility for several years.3 The plaintiffs alleged that they were convicted

due to incorrect Intoxilyzer readings, and they averred that the District had

announced on February 26, 2010, its awareness of “a potential problem with the

accuracy of the [Intoxilyzer] machines.” Id. at 7-8. The convictions of most of the

      3
         The responsibility for calibration and testing initially had been assigned to
the Office of the Medical Examiner, but around February 2007, the responsibility
was delegated to MPD’s Impaired Driver Support Unit. Molina-Aviles, supra, 824
F. Supp. 2d at 6-7 & n.5.
                                           6

plaintiffs were vacated or dismissed in the Superior Court. On November 14,

2011, the district court denied Officer King’s motion to dismiss, without prejudice.

Id. at 6.



     At some point prior to the FOIA request in this case, MPD hired a consultant,

Ilmar Paegle, to assist with the breathalyzer program. Mr. Paegle determined that

the Intoxilyzer was giving inaccurate readings. In response to the controversy

concerning the accuracy of the Intoxilyzer readings MPD opened an investigation,

focusing on Officer King, and FOP sought documents relating to the Intoxilyzer.4



       FOP submitted its FOIA request to MPD and the Office of the Chief

Technology Officer (“OCTO”) on April 21, 2010. FOP asked for nine categories

of materials, and its letter specifically referenced Officer King:



             1.   Any and all documents from October 1, 2008 to
                  April 1, 2010, related to any quality control
                  problems, and or calibration problems with the
                  Intoxilyzer 5000EN[] utilized by the Metropolitan
                  Police Department.


       4
         The investigation concluded with a finding of insufficient evidence to
sustain any allegations of misconduct against any MPD officer. The report
recommended that MPD develop “best calibration procedures” for the Intoxilyzer,
as well as a program to train its personnel in those procedures.
                            7

2.   Any and all documents sent from the [MPD] to the
     District of Columbia’s Attorney[] General[’s] Office
     related to any quality control problems, and or
     calibration problems with the Intoxilyzer 5000EN[]
     utilized by the [MPD] from October 1, 2008 to April
     1, 2010.
3.   Any and all documents, emails, and attachments sent
     or received, from Assistant Chief Patrick Burke’s
     [MPD] email address [] from October 1, 2008 to
     April 1, 2010, relevant to the [MPD] Intoxilyzer
     5000EN.
4.   Any and all documents, emails, and attachments sent
     or received, from Assistant Chief Patrick Burke’s
     [MPD] email address [] from October 1, 2008 to
     April 1, 2010, related and relevant to any quality
     control problems, and or calibration problems with
     the MPD’s Intoxilyzer 5000EN.
5.   Any and all documents, emails, and attachments sent
     or received, from Assistant Chief Patrick Burke’s
     [MPD] email address [] or any member of his staff,
     to the Office of the Attorney General[’s] Office,
     related and relevant to any quality control problems,
     and or calibration problems with the MPD’s
     Intoxilyzer 5000EN from October 1, 2008 to April
     1, 2010.
6.   Any and all documents, emails and attachments sent
     or received from Mr. James Austrich’s [MPD] email
     address [] from October 1, 2008 to April 1, 2010,
     related to any quality control problems with the
     Intoxilyzer 5000EN.
7.   Any and all documents, emails and attachments sent
     or received from Mr. Ilmar Paegle’s [MPD] email
     address [] from October 1, 2008 to April 1, 2010,
     related to any quality control problems, and or
     calibration problems with the MPD’s Intoxilyzer
     5000EN.
8.   Any and all documents, emails and attachments sent
     or received BETWEEN Mr. Ilmar Paegle’s [MPD]
     email address [] AND Assistant Chief Patrick
                                        8

                  Burke’s [MPD] email address [] from October 1,
                  2008 to April 1, 2010.
            9.    Any and all documents, emails and attachments sent
                  or received BETWEEN Mr. Ilmar Paegle’s [MPD]
                  email address AND Officer Kelvin King’s [MPD]
                  email address [] from October 1, 2008 to April 1,
                  2010.



      Natasha Cenatus, MPD’s FOIA officer, sent FOP’s FOIA request to MPD’s

Homeland Security Bureau and MPD’s Internal Affairs Bureau.             She also

contacted the FOIA liaison person in both of those Bureaus, Traci Dean and

Carnelia Austin, respectively. Ms. Dean informed Ms. Cenatus that Assistant

Chief Burke, Mr. Paegle, James Austrich, and Officer King, the persons

specifically mentioned in the FOIA request, were searching their “computer hard

drive[s], archived e-mail files, paper files and any other records located in or

around their office[s],” for responsive documents.      Ms. Austin advised Ms.

Cenatus that persons in Internal Affairs were conducting a search “for any

investigative documents related to [FOP’s] FOIA request.” Subsequently, Ms.

Austin reported that “the investigation concerning the Intoxilyzer 5000EN and the

employees [named in the FOIA request] was still an open investigation and . . . no

information could be released to the public until the investigation was completed

and closed.”     On May 11, 2010, the day after she received word that the
                                           9

investigation was ongoing, Ms. Cenatus prepared a denial letter to FOP and a

“Vaughn Index.”



      In her May 11 letter to FOP denying its FOIA request, Ms. Cenatus stated,

in pertinent part:   “Unfortunately, your request for records maintained by the

[MPD] is denied pursuant to D.C. Code [§] 2-534 (a)(3): See Vaughn Index

attached.”5   The Vaughn Index comprised one page.              That page referenced

“documents/emails related to Intoxilyzer 5000EN,” dated “October 2, 2008 – April

1, 2010.” The documents were classified as “Confidential.” The Vaughn Index

also listed the FOIA statutory exemptions by subsection, and an “X” had been

placed on the line designating “(a)(3).” The following narrative was the last entry

on the Vaughn Index: “D.C. Code 2-534(a)(3)(A): ‘This information is currently

under an ongoing investigation with the [MPD]’s Internal Affairs. This document

contains records compiled for law-enforcement purposes and such disclosures

would interfere with enforcement proceedings, [C]ouncil investigations, OPC


      5
         Prior to the salutation of the District’s letter, the subject was identified as
an “FOIA Request for information related to quality control problems and/or
calibration problems with the MPD Intoxilyzer 5000EN . . .,” but the first sentence
of the letter stated: “This is to inform you that we received your Freedom of
Information Act requesting [sic] data or audio recording of the shot spotter
device.” The reference to the “shot spotter device” appears to be an inadvertent
error.
                                          10

ongoing investigations.’” The May 11 letter also stated: “Please know that, under

D.C. Official Code § 2-537 and 1 DCMR 412, you have the right to appeal this

letter to the Mayor or the Superior [C]ourt of the District of Columbia.” The

District’s May 11 response to FOP’s FOIA request fell within the statutory

response time.6



      Approximately two months after receiving the May 11 letter, FOP filed a

complaint against the District in the Superior Court. The July 12, 2010, complaint

asked the trial court to: (1) “declare that the [District’s] failure to adequately

respond to the FOIA [r]equest submitted by the [FOP] is unlawful, arbitrary and

capricious”; (2) “compel the [District] to produce any and all of the information

requested through the FOIA [r]equest . . . within fourteen (14) days of an [o]rder

signed by [the trial] [c]ourt”; and (3) “award to the [FOP] its attorneys’ fees and

costs associated with this action in accordance with D.C. Code . . . § 2-537 (c). . ..”



      The District answered FOP’s complaint on October 15, 2010. In addition to

its general denial, the District asserted several defenses, including the following:


      6
         D.C. Code § 2-532 (c) provides that the District shall respond to all FOIA
requests within fifteen working days by either making the requested public records
available or notifying the party making the request of the determination that the
request had been denied and providing the reasons in support of that determination.
                                          11

“The District is entitled to withhold documents pursuant to D.C. Code § 2-534, et

seq.”



        On October 26, 2010, while FOP’s complaint was still pending, the District

sent a letter to FOP, together with 119 pages of material described as “responsive

documents,” some of which “ha[d] been redacted in order to preserve privacy

subject to D.C. Code § 2-534(a)(2). . . .” The District also attached “a Vaughn

Index, identifying privileged documents.” The transmittal letter concluded with

the following statement: “As responsive documents, initially withheld due to an

ongoing police investigation, have now been produced, we request that FOP

stipulate to a dismissal of this case.”



        The October 26 production was augmented by a second document

production on November 23, 2010, consisting of 139 documents and a Vaughn

Index, identifying privileged documents.       The District asserted the following

privileges: attorney-client, work product, and deliberative process. In response to

FOP’s inquiry as to whether the document production was complete, the District

stated, in part, on November 24, 2010: “We recently received additional emails

that must be reviewed before we can state that what was produced yesterday is the

final production in the FOIA matter.”
                                         12

      The FOP filed a motion for summary judgment on December 7, 2010,

challenging the adequacy of the District’s document production. FOP also argued

that there were deficiencies in the Vaughn indices, including the lack of affidavits

to support the claim for exemption based on privilege.7



      During a December 10, 2010, status conference, the District announced that

(1) it would “respond in due course” to FOP’s summary judgment motion, and (2)

in its search for documents in other “breathalyzer cases,” conducted at the direction

of litigation counsel, the Chief Technology Officer had produced 40,000 emails.

The District had reviewed 8,000 of the emails, found 240 to be responsive to

FOP’s request, and needed more time to review the remainder of the emails. On

January 5, 2011, the District filed both its opposition to FOP’s summary judgment

motion, and its cross-motion for summary judgment.           Thereafter, the parties

continued to file pleadings relating to the summary judgment motions.




      7
         FOP argued, in part, that the District did not provide “any of the required
[a]ffidavit evidence to support” its assertion of the deliberative process privilege.
Documents withheld on the basis of the deliberative process privilege included an
email from Michael Anzallo to Christopher Lojacono, George Dixon, Samuel
Golway, and Richard Brady, all of MPD; the email was described as “Discussion
between policy-makers re calibration problem and how to address it.”
                                          13

      On April 7, 2011, the District forwarded additional documents (871 pages of

material) to FOP, along with a thirteen-page Vaughn Index, listing and describing

documents, and invoking various privileges – work product, deliberative process,

and attorney-client. At the conclusion of its cover transmittal, the District asserted:

“Please note that this production satisfies the District’s agreement to provide to

you additional documentation responsive to the FOP’s FOIA request and is not

made pursuant to any requirement under the FOIA statute.”              Apparently no

affidavits accompanied the April 7 production.8



      The trial court requested supplemental pleadings in June and July 2011,

focusing on whether the District’s May 2010 response to FOP’s FOIA request

violated the Act. FOP filed its supplement on June 24, 2011, challenging the

District’s use of the investigatory records exemption. The District responded on

July 15, 2011, justifying its reliance on the investigatory records exemption,


      8
        The District argued in its May 5, 2011, supplement to its motion for
summary judgment that FOP was “not entitled under FOIA to any of the material
produced on April 7, 2011, because the District fulfilled its obligations under
FOIA with its initial response to FOP on May 11, 2010,” and “[t]he only reason
[FOP] is receiving any additional documents at all is because (1) [FOP] made its
FOIA request concurrent with the Breathalyzer litigation, a series of lawsuits
regarding similar subject matter; and (2) upon review of documents collected for
the Breathalyzer litigation, counsel have discovered documents that are responsive
to [FOP’s] FOIA request.” The District said the same was true regarding its
October and November document productions.
                                         14

reiterating its subsequent document production, and claiming that the case was

now moot. FOP’s July 26, 2011, response again (1) contended that the District

resorted to an impermissible assertion of a blanket exemption, stated that the

District’s response to the FOIA request was untimely and the October, November,

and April document productions were immaterial to the initial denial of FOP’s

request, and (2) characterized the District’s mootness argument as “frivolous”

because, as of June 16, 2011, the District admitted that it had not produced all

responsive documents. Furthermore, FOP asserted, “even if the production were

complete, which it is not, the District’s production does not address the declaratory

relief sought through this action.”



      The court held hearings on the summary judgment issues on June 16, 2011,

July 29, 2011, and September 23, 2011. The June 16, 2011, substantive hearing

constituted a wide-ranging discussion of issues presented by FOP and the District,

including the proper interpretation of the District’s FOIA statute, the privileges

invoked by the District during its responses to FOP’s FOIA request, the necessity

for exhausting administrative remedies, the inadequacy of the initial response, the

deficiencies in the Vaughn Indices, the complications presented by discovery in

other ongoing breathalyzer civil cases, and the issue of whether the District had a

continuing obligation to produce responsive documents after the Intoxilyzer
                                          15

investigation had ended. The trial court appeared most interested in the adequacy

of the District’s initial response, whether the District wrongfully withheld

documents when it responded on May 11, 2010, and whether the District had an

ongoing obligation to produce documents after its initial response. The July 29,

2011, hearing concerned a procedural matter.            The September 23, 2011,

substantive hearing examined the alleged blanket investigatory records exemption

claimed by the District, the completeness of the District’s document production,

and the privileges asserted by the District in its post-May 11, 2010, transmittals.



      The trial court denied FOP’s motion for summary judgment and the

District’s cross-motion for summary judgment on October 18, 2011. The court

rejected the District’s assertion that FOP failed to exhaust its administrative

remedies.   In addition, the court concluded that the issue as to whether the

District’s “original document production was valid,” required further development

of the record regarding whether the District claimed an impermissible “blanket

exemption” or “a permissible ‘generic determination.’” The trial court viewed the

blanket exemption assertion as a “critical issue” that should be decided by the

“trier of fact.” The District filed a partial consent motion for reconsideration in

November 2011, and FOP filed a motion for reconsideration.
                                         16

      On February 24, 2012, the trial court denied FOP’s motion for

reconsideration, granted the District’s motion for summary judgment, and

dismissed FOP’s complaint. The trial court declared “that the sufficiency of the

investigatory records exemption is a matter of law, rather than one of fact,” and

hence, that issue could be resolved by the court. The court ruled that the District

“submitted a valid generic determination because the [c]ourt can trace a rational

link between ‘documents’ discussing problems and complaints with the Intoxilyzer

and the ‘interference,’ with the progress of an ongoing investigation relating to the

Intoxilyzer.” After referencing affidavits submitted by Assistant Chief Burke and

Ms. Cenatus,9 and following its consideration of “the substance of the [District’s]

response to the FOIA request,” the trial court asserted that the exemption claimed

by the government was ‘functional,’” and that the court could “trace a rational link

      9
         In his declaration of January 5, 2011, Assistant Chief Burke stated that he
“personally reviewed the documents listed in the two Vaughn Indices, . . . and
marked deliberative privilege.” He further asserted that “these documents reflect
pre-decisional deliberations among policy-makers regarding various policies,
including the policy regarding Intoxilyzer machines.” Also included were “drafts
of calibration and accuracy reports.” He added: “I believe that the disclosure of
the referenced documents would seriously discourage government employees from
communicating with the candor necessary to effectively carry out their
responsibilities.” The declaration does not mention any of the individuals
referenced in FOP’s document request. In her declaration of January 4, 2011, Ms.
Cenatus said, in part, that on May 10, 2010, she “was verbally informed by Ms.
Austin . . . that the investigation concerning the Intoxilyzer 5000EN and [Officer
King, Mr. Paegle, Mr. Austrich, and Assistant Chief Burke] was still an open
investigation and that no information could be released to the public until the
investigation was completed and closed.”
                                           17

between the ways in which disclosure of the requested documents would interfere

with the District’s Intoxilyzer investigation.” The court added that “although not

directly relevant to [its] analysis, it is worth noting that [the District] ultimately did

continue to respond to the FOIA request upon the conclusion of the investigation

and thereafter, even though it was not required to do so.” The court did not accept

FOP’s argument that the District “prematurely and improperly invoked its

exemption,” because FOP failed to “provide any evidence supporting the allegation

that the [District] knew when the investigation would close or that the [District]

intentionally made its FOIA response earlier in order to avoid producing the

investigation documents after the investigation closed.” The court did not address

the District’s mootness contention.



                                      ANALYSIS



      The Arguments of the Parties



      At the beginning of its argument, FOP notes that “the parties briefed

numerous issues relating to the District’s multiple productions of documents . . . ,”

but that “the Superior Court narrowed the consideration to the discrete issue of

whether the District supported its initial claim to the investigatory records
                                         18

exemption under the FOIA” in its response of May 11, 2010. FOP contends that

the Superior Court improperly granted the District’s motion for summary judgment

on the narrow issue of whether the District supported its initial claim to the

investigatory records exemption under D.C. Code § 2-534 (a)(3)(A), and that

“[t]he trial court erred in concluding that [the District’s] blanket assertion of the

[investigatory] exemption was supported under the [District’s] FOIA based upon

belated production of documents that the District provided after the initiation of

litigation in this action, and the belated [a]ffidavits submitted by the District in

support of their actions. . . .” FOP further insists that the District failed to: (1)

“provide the Superior Court with a basis to infer that the disclosure of [drafts of

calibration accuracy reports, mentioned in Assistant Chief Burke’s affidavit] would

have interfered with any ongoing investigation” at the time it claimed the

investigatory records exemption on May 11, 2010, (2) “engage in a document-by-

document review,” and (3) “identify categories of documents to support a generic

claim to the [investigatory records] exemption.” FOP claims that the District’s

“voluntary” production of documents “that it claimed to be outside of the scope of

the FOIA Request did not cure this . . . FOIA violation.”



      The District urges that the case is moot because the government voluntarily

produced all non-exempt documents requested by FOP. Furthermore, the District
                                          19

claims that “FOP challenges only the adequacy of MPD’s initial response to the

FOIA request and does not challenge whether MPD’s production as a whole was

legally adequate.” Moreover, the District argues that “FOP did not ask the court to

resolve any disputed facts about whether production was complete or the Vaughn

indices adequately documented the claimed exemptions and redactions.”           The

District further maintains that FOP “does not argue on appeal [] that the law-

enforcement exception does not apply here in light of MPD Internal Affairs’

investigation of Officer King,” and rather, confines its argument to the assertion

that the District “claimed the exemption ‘without a proper and complete

explanation or any of the required backup information.’” The District supports the

trial court’s conclusion that it “claimed a valid and ‘functional’ exemption,” based

on its investigation about the Intoxilyzer.



      In its reply brief FOP takes issue with the District’s contention that it

“provided all of the documents responsive to the FOIA Request”; FOP responds:

“The District is simply incorrect.” Furthermore, FOP states that even assuming

“the District did provide all of the responsive documents,” it did not respond

within the fifteen-day required statutory period, and that FOP “had an absolute

right to receive within fifteen (15) days of the District’s receipt of the FOIA

[r]equest” the documents requested or “notification of denial of access with
                                          20

explanation of ‘the reasons therefore’ and support for those reasons.”            FOP

cautions that if this court does not follow the statutory time limit, the required 15-

day response provision would become “meaningless,” and such a ruling “would

discourage FOIA requests by allowing the District to embroil FOIA requestors in

litigation before escaping liability by simply providing a tardy response.”         In

addition, FOP argues, and reiterates its position, that neither the declaration

provided by Assistant Chief Burke nor that submitted by Ms. Cenatus provides

support for the District’s assertion of the investigatory records exemption. The

Burke declaration, submitted after the District began producing documents, “is

specifically focused on the deliberative process privilege and is utterly silent on the

issue of investigatory records”; the Cenatus declaration “does not show that the

District defined its documents categorically, conducted a document-by-document

search or explained how the release of the documents would interfere with an

investigation.”



      Legal Standards and Principles



      We now set forth the legal standards and principles that guide our analysis.

Our review of the trial court’s grant of summary judgment to the District is de

novo. Fraternal Order of Police v. District of Columbia, No. 12-CV-1476, 2013
                                         21

D.C. App. LEXIS 779, at *8 (D.C. Nov. 7, 2013). We view the record in the light

most favorable to the party opposing summary judgment.” Id. (citation omitted).

“Summary judgment is appropriate only when the record, including pleadings

together with affidavits, indicates that there is no genuine issue as to any material

fact and that the moving party is entitled to judgment as a matter of law.” District

of Columbia v. Fraternal Order of Police, 75 A.3d 259, 266 (D.C. 2013) (quoting

Padou v. District of Columbia, 29 A.3d 973, 980 (D.C. 2011)) (internal quotation

marks omitted). We determine “whether the agency has sustained its burden of

demonstrating the documents requested are exempt from disclosure under the

FOIA.” Id. (quoting Multi AG Media LLC v. Department of Agric., 380 U.S. App.

D.C. 1, 4, 515 F.3d 1224, 1227 (2008)) (internal quotation marks omitted).



      Given the broad disclosure policy reflected in the District’s FOIA, we

“construe[] [the Act] with the view toward expansion of public access and the

minimization of costs and time delays to persons requesting information.”

Fraternal Order of Police v. District of Columbia, supra, 2013 D.C. App. LEXIS

779, at *9 (citing D.C. Code § 2-531 (2012 Repl.)). “Therefore, ‘the provisions of

the Act giving citizens the right of access are to be generously construed, while the

statutory exemptions from disclosure are to be narrowly construed, with
                                         22

ambiguities resolved in favor of disclosure.” Id. at *9-10 (quoting Riley v. Fenty, 7

A.3d 1014, 1018 (D.C. 2010)).



       Generally, a case is moot “when the issues presented are no longer ‘live’ or

the parties lack ‘a legally cognizable interest in the outcome.’” Settlemire v.

District of Columbia Office of Emp. Appeals, 898 A.2d 902, 904-05 (D.C. 2006)

(citation omitted). “[W]hile an appeal is pending, an event that renders relief

impossible or unnecessary also renders that appeal moot.” Id. at 905 (quoting

Vaughn v. United States, 579 A.2d 170, 175 n.7 (D.C. 1990)). “In general, ‘once

the government produces all the documents a plaintiff requests, [the] claim for

relief under the FOIA becomes moot.” Walsh v. United States Dep’t of Veterans

Affairs, 400 F.3d 535, 536 (7th Cir. 2005) (quoting Anderson v. United States

Dep’t of Health & Human Servs., 3 F.3d 1383, 1384 (10th Cir. 1993) (other

citations omitted)); Mullen v. United States Army Criminal Investigation

Command, 1:10cv262 (JCC/TCB), 2010 U.S. Dist. LEXIS 58939, at *8 (E.D. Va.

June 14, 2010) (where agency agreed to produce requested documents within two

weeks, question as to whether they were withheld under the law enforcement

exemption is moot).     However, “in instances where an agency has released

documents, but other related issues remain unresolved, courts frequently will not

dismiss the action as moot.” McKinley v. Federal Deposit Ins. Corp., 756 F. Supp.
                                         23

2d 105, 110 (D.D.C. 2010) (internal quotation marks and citations omitted).

Mootness is a question of law which we review de novo. See Walsh, supra, 400

F.3d at 536.



      “In a FOIA case, the burden of proof is always on the agency to demonstrate

that it has fully discharged its obligations under the FOIA.” McKinley, supra,

2010 U.S. Dist. LEXIS 135965, at *6-7 (quoting Department of Justice v. Tax

Analysts, 492 U.S. 136, 142 n.3 (1989)). Moreover, “the standard for determining

whether a case or controversy is mooted by a defendant’s voluntary conduct is

‘stringent.’” Northwestern Univ. v. United States Dep’t of Agric., 403 F. Supp. 2d

83, 85 (D.D.C. 2005). Consequently, “[i]n determining mootness, the court has to

make ‘absolutely clear that the allegedly wrongful behavior could not reasonably

be expected to recur.’” Id. (quoting Friends of the Earth v. Laidlaw, 528 U.S. 167,

189 (2000)). “The movant must also show that ‘interim relief and events have

completely and irrevocably eradicated the effects of the alleged violation.’” Id.

(citation omitted). “The court . . . retains jurisdiction of a FOIA case if it is not

convinced that the agency has released all nonexempt material.” Id. at 86 (citing

Perry v. Block, 221 U.S. App. D.C. 347, 351, 684 F.2d 121, 125 (1982)).
                                         24

        The Investigatory Records Exemption



        The District’s FOIA exemption for investigatory records is modeled on the

corresponding exemption in the federal FOIA, 5 U.S.C. § 552 (b)(7)(A) (2012).10


        10
          5 U.S.C. § 552 (a) sets forth the federal disclosure policies, and 5 U.S.C.
§ 552 (b) contains the statutory exemptions:

              § 552. Public information; agency rules, opinions,
              orders, records, and proceedings
              (a) Each agency shall make available to the public
              information as follows:

              ....

              (b) This section does not apply to matters that are—

 ....

              (7) records or information compiled for law enforcement
              purposes, but only to the extent that the production of
              such law enforcement records or information (A) could
              reasonably be expected to interfere with enforcement
              proceedings, (B) would deprive a person of a right to a
              fair trial or an impartial adjudication, (C) could
              reasonably be expected to constitute an unwarranted
              invasion of personal privacy, (D) could reasonably be
              expected to disclose the identity of a confidential source,
              including a State, local, or foreign agency or authority or
              any private institution which furnished information on a
              confidential basis, and, in the case of a record or
              information compiled by criminal law enforcement
              authority in the course of a criminal investigation or by
              an agency conducting a lawful national security
              intelligence investigation, information furnished by a
                                                                        (continued…)
                                         25

Barry v. Washington Post Co., 529 A.2d 319, 321 (D.C. 1987). After recognizing

that FOIA statutory exemptions must be read “narrowly” to safeguard “the strong

public policy favoring disclosure about governmental affairs and the acts of public

officials,” this court “h[e]ld that the phrase ‘investigatory records compiled for

law enforcement purposes’ in exemption 3 [of the District’s FOIA] refers only to

records prepared or assembled in the course of ‘investigations which focus directly

on specifically alleged illegal acts, illegal acts of particular identified [persons],

acts which could, if proved, result in civil or criminal sanctions.’” Id. at 321-22

(quoting Rural Hous. Alliance v. United States Dep’t of Agric., 162 U.S. App. D.C.

122, 130, 498 F.2d 73, 81 (1974)) (third alteration in original). Thus, to satisfy

D.C. Code § 2-534 (a)(3)(A)(i), investigatory records compiled for law

enforcement purposes that would interfere with enforcement proceedings, the

District has the burden of showing: (1) the documents requested by FOP have

been “compiled for law enforcement purposes,” and (2) disclosure of those



(…continued)
           confidential source, (E) would disclose techniques and
           procedures for law enforcement investigations or
           prosecutions, or would disclose guidelines for law
           enforcement investigations or prosecutions if such
           disclosure could reasonably be expected to risk
           circumvention of the law, or (F) could reasonably be
           expected to endanger the life or physical safety of any
           individual. . . .
                                        26

documents would “interfere with enforcement proceedings.” Bevis v. Department

of State, 801 F.2d 1386, 1388 (D.C. Cir. 1986).



      What Congress meant by interference with enforcement proceedings was

“the release of information in investigatory files prior to the completion of an

actual, contemplated enforcement proceeding.” National Labor Relations Bd. v.

Robbins Tire & Rubber Co., 437 U.S. 214, 232 (1978).            “[S]o long as the

investigation continues to gather evidence for a possible future criminal case, and

that case would be jeopardized by the premature release of the evidence, [the

investigatory records exemption] applies.” Juarez v. Department of Justice, 518

F.3d 54, 59 (D.C. Cir. 2008). However, “where an agency fails to [demonstrate]

that the . . . documents [sought] relate to any ongoing investigation or . . . would

jeopardize any future law enforcement proceedings, [the investigatory records

exemption] would not provide protection to the agency’s decision.” Robbins Tire

& Rubber Co., supra, at 235 (alterations in original) (internal quotation marks and

citation omitted).



      A “blanket exemption,” that is, “an exemption claimed for all records in a

file simply because they are in a file,” is impermissible under the investigatory

records exemption. Crooker v. Bureau of Alcohol, Tobacco & Firearms, 789 F.2d
                                           27

64, 66 (D.C. Cir. 1986). But, “courts [may] make generic determinations that with

respect to particular kinds of enforcement proceedings, disclosure of particular

kinds of investigatory records . . . would generally interfere with enforcement

proceedings.” Id. at 67 (quoting Robbins Tire & Rubber Co., supra, 437 U.S. at

236) (internal quotation marks omitted).



      Under a generic approach, an agency justifies its non-disclosure of

documents as investigatory records based on a functional category (or categories)

that “allows the court to trace a rational link between the nature of the document

and the alleged likely interference.” Id. In that regard, the agency has a “three-

fold task”; it must:   (1) “define its categories functionally,” (2) “conduct a

document-by-document review in order to assign documents to the proper

category,” and (3) “explain to the court how the release of each category would

interfere with enforcement proceedings.” Bevis, supra, 801 F.2d at 1389-90. An

agency must sustain its burden “by identifying a pending or potential law

enforcement proceeding or providing sufficient facts from which the likelihood of

such a proceeding may reasonably be inferred.” Durrani v. United States Dep’t of

Justice, 607 F. Supp. 2d 77, 90 (D.D.C. 2009) (citation omitted). “If the generic

index submitted by the government is not sufficient to sustain the [investigatory

records exemption], then the [trial] court may request more specific, distinct
                                         28

categories so that it may more easily determine how each category might interfere

with enforcement proceedings”; “[t]he chief characteristic of an acceptable

taxonomy should be functionality — that is, the classification should be clear

enough to permit a court to ascertain how each . . . category of documents, if

disclosed, would interfere with the investigation.” Crancer v. United States Dep’t

of Justice (In re Department of Justice), 999 F.2d 1302, 1310 (8th Cir. 1993)

(internal quotation marks and citations omitted).



      The District’s Assertion of Mootness



      Mootness is a justiciability issue which implicates the power of the court to

entertain the lawsuit.11 We first consider the District’s argument that this case is

moot because the government voluntarily produced documents responsive to

FOP’s request. The trial court did not address the question of mootness despite the

fact that the District explicitly raised it on July 15, 2011, in its supplemental

pleading requested by the court. In its supplemental pleading, the District stated:

“By providing [FOP] with a complete response no later than October 26, 2010, and


      11
         Because this court is not an Article III court, the constitutional “case or
controversy” requirement is not directly applicable to us; nevertheless, we
generally choose to adhere to federal mootness principles. See, e.g., Saucier v.
Countrywide Home Loans, 64 A.3d 428 (D.C. 2013).
                                          29

even taking into account the later, supplemental productions, the District has

mooted the controversy.” FOP took issue in the trial court with the District’s

assertion of mootness, arguing in its July 26, 2011, pleading that the mootness

argument was “frivolous,” and that the case was not moot, not only because there

remained an outstanding question as to whether the District’s document production

was complete, but also because “even if the production were deemed complete,

significant legal issues would still remain unresolved,” including FOP’s request for

declaratory relief and the timeliness of the District’s response.



      On appeal, the District contends that: “Regardless of the propriety of the

District’s original response to the FOIA request invoking a generic law

enforcement exception to production based on the then-ongoing internal MPD

investigation, this case is now moot because the District subsequently produced all

requested documents,” and hence, “FOP received all the non-exempt documents it

sought in this FOIA action.” The District further maintains that (1) a case is moot

“even where an agency’s initial response was tardy or incomplete,” (2) “FOP’s

‘desire for vindication,’ a declaration that the original denial was improper, is

‘inadequate’ to create a live controversy and thus prevent a finding of mootness,”

(3) its claim of mootness “‘is not overcome by [FOP’s] interest in being awarded

attorney’s fees,’” (4) this court should not exercise its discretion under the “capable
                                        30

of repetition, yet evading review” doctrine because “[t]he precise issue FOP

presses is fact-bound, turning on the particulars of MPD’s initial response to the

FOIA request” and because “FOP did not preserve its entitlement to ask for such

an exercise of discretion,” and (5) “FOP did not ask the court to resolve any

disputed facts about whether production was complete or the Vaughn indexes

adequately documented the claimed exemptions and redactions.”



      Our review of the record satisfies us that this case is not moot. The District

asserts that an agency’s production of all requested, non-privileged documents

generally moots a FOIA case or controversy. See Walsh, supra, 400 F.3d at 536.

While that is true, the problem here is that the trial court has not determined

whether the District has sustained its FOIA burden by disclosing all of the

requested documents to which FOP is entitled, even though the District contended

in the trial court that it has produced all responsive documents, and in contrast,

FOP questioned the adequacy of the District’s production. Hence, we cannot agree

that the case is moot.12


      12
         FOP maintains in its reply brief that the District’s initial response was
untimely. We addressed the timeliness issue in Fraternal Order of Police v.
District of Columbia, supra, 2013 D.C. App. LEXIS 779, at *37-39. There, we
rejected FOP’s timeliness argument, distinguishing between “timeliness” and
“sufficiency.” We concluded that the District’s response was timely because it
“responded in good faith to a FOIA request within the time prescribed by the
                                                                      (continued…)
                                          31

      Nor can we agree with the District’s contention that FOP has forfeited its

challenge to the adequacy of the disclosures that the District made subsequent to its

initial response to FOP. Not only did FOP challenge the adequacy of the District’s

subsequent document production in the trial court, but in its reply brief on appeal

and in response to the District’s argument concerning mootness, FOP reiterated its

position that the District’s disclosure was inadequate. Thus, we cannot say on this

record that FOP forfeited its challenge to the District’s subsequent document

production.



      The Summary Judgment Motion



      We are constrained to hold that the grant of summary judgment to the

District was improper because the trial court committed an error of law.

Specifically, the trial court erred in determining as a matter of law that the District

“submitted a valid generic determination” with respect to its initial response based

on the investigatory exemption. The court based this conclusion on the Burke and

(…continued)
statute, enabling the requestor to seek relief in court for any perceived deficiencies
such as the inadequacy of the agency’s search for responsive documents or the
unavailability of a claimed exemption.” Id. at *38-39. Here, the District’s initial
response to FOP’s FOIA request fell within the statutory 15-day period, and hence,
it was timely. In addition, FOP does not contend on appeal that the District acted
in bad faith.
                                          32

Cenatus declarations, and asserted that the court could “trace a rational link

between ‘documents’ discussing problems and complaints with the Intoxilyzer and

the ‘interference,’ with the progress of an ongoing investigation relating to the

Intoxilyzer.”    However, the District’s May 11, 2010, letter contains only one

substantive sentence: “Unfortunately, your request for records maintained by the

[MPD] is denied pursuant to D.C. Code § 2-532 (a)(3):            See Vaughn Index

attached.”      The accompanying Vaughn Index consisted of one page and the

District did not submit any explanatory affidavits or declarations. The Vaughn

Index     identified    the   “subject”    as    “documents/emails      related    to

problems/complaints involved with MPD’s use of Intoxilyzer 5000EN,”

presumably the category of documents for which the District was claiming the

investigatory records exemption. With respect to how disclosure of this category

of documents would interfere with law-enforcement proceedings under D.C. Code

§ 2-534 (a)(3)(A)(i), the District included one sentence: “This document contains

records compiled for law-enforcement purposes and such disclosure would

interfere with enforcement proceedings, [C]ouncil investigations, OPC ongoing

investigations.”



        As we said in Fraternal Order of Police v. District of Columbia, supra, the

“omission [of an affidavit or declaration] was not necessarily fatal,” because “[t]he
                                          33

District can satisfy its burden to provide ‘a sufficiently detailed description of what

it is refusing to produce and why’ by including all the necessary information on a

Vaughn Index alone”; however, “the index must supply enough information to

enable the court to assess whether the District properly invoked the privilege.” Id.

2013 D.C. App. LEXIS 779, at *23 (quoting Fiduccia v. Department of Justice,

185 F.3d 1035, 1042 (9th Cir. 1999)). Here, the Vaughn Index submitted by the

District on May 11, 2010, was insufficient because it contained only one

conclusory statement that repeated statutory language, and that did not “enable the

[trial] court to assess the propriety of the District’s decision to withhold the

material.” Id. at *24. Indeed, the Vaughn Index offered no insight into the specific

documents that the District was withholding. While we can infer from the Vaughn

Index     that   the   functional   category   is   “documents/emails     related    to

problems/complaints involved with MPD’s use of Intoxilyzer 5000En,” it is not

clear that the District “conduct[ed] a document-by-document review” to make

certain that all documents withheld fell into that category; nor does the Vaughn

Index “explain to the court how the release of this category of documents would

interfere with enforcement proceedings.” Bevis, supra, 801 F.2d at 1390.



        In reaching its conclusion that the District satisfied all of the Crooker

requirements for a generic determination, the trial court relied on the January 2011
                                         34

declarations of Assistant Chief Burke and Ms. Cenatus. The substance of the

Burke declaration was limited to one page, made no mention of any investigation,

and covered only the October 26 and November 23, 2010, documents for which the

“deliberative process privilege” was asserted. Moreover, the Burke declaration

said nothing about interference with a law-enforcement proceeding, and instead,

stated that “the disclosure of the referenced documents would seriously discourage

government employees from communicating with the candor necessary to

effectively carry out their responsibilities,” an apparent effort to show that the

deliberative privilege applied. Unlike Assistant Chief Burke, who was responsible

for oversight of MPD’s Special Operations Division and Tactical Information

Divisions, Ms. Cenatus as MPD’s FOIA officer had no personal knowledge about

the Intoxilyzer or the District’s investigation, and she specifically stated in her

declaration that she “did not personally review [documents sent to her by the

District on August 25, 2010, and September 27, 2010] to determine which ones, if

any, would be responsive to the FOIA search.” Under these circumstances, the

District was not entitled to summary judgment as a matter of law.



      Furthermore, the question as to whether the District released all non-

privileged documents after its initial denial, as it contends, presents genuine issues

of material fact, even considering the Burke and Cenatus declarations. The Burke
                                          35

and Cenatus declarations were submitted prior to the District’s April 7, 2011,

disclosures for which it claimed various privileges. Apparently, no explanatory

declaration was submitted with the April 7, 2011, document production, and in

several instances for documents referenced prior to April 2011, the Index does not

demonstrate why the documents are shielded from disclosure by privilege. For

example, several documents generated between February and March 2010, are

“forms” described as “draft calibration and accuracy checklist” for which the

District asserts the deliberative process privilege, but it is not readily apparent why

these forms implicate the deliberative process. We explained the deliberative

process privilege in Fraternal Order of Police v. District of Columbia, supra,

indicating that the information withheld under this privilege “must be both

‘predicisional’ and ‘deliberative,’” that is, it must have been “prepared in order to

assist an agency decision maker in arriving at his decision,” and “reflect[] the give

and take of consultative process.” 2013 D.C. App. LEXIS 779 at *12. The

description of the documents as “draft calibration and accuracy checklist” does not

“pinpoint an [MPD] decision or policy to which these [forms] contributed,” nor is

one able to infer from the Vaughn Index that the forms were part of a consultative

process. Id. at *12-13.
                                        36

       Accordingly, because (1) the case is not moot, (2) FOP has not forfeited its

challenge to the adequacy of the District’s disclosures subsequent to its initial

response to FOP’s document request, and (3) the trial court improperly granted

summary judgment to the District, we vacate the trial court’s order and remand this

case so that the trial court may (a) consider the implications of the District’s

subsequent document production, and (b) resolve the merits of the dispute, whether

(i) by way of summary judgment under a proper understanding of the relevant legal

principles or (ii) after a trial.



                                             So ordered.
