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SJC-11981

                COMMONWEALTH   vs.   ADMILSON RESENDE.



            Plymouth.    April 4, 2016. - July 25, 2016.

 Present:    Gants, C.J., Spina, Cordy, Botsford, Duffly, Lenk, &
                             Hines, JJ.


Controlled Substances. Constitutional Law, Plea, Conduct of
     government agents. Due Process of Law, Plea, Disclosure of
     evidence, Presumption. Practice, Criminal, Plea, New
     trial, Conduct of government agents, Disclosure of
     evidence, Presumptions and burden of proof. Evidence,
     Guilty plea, Certificate of drug analysis, Presumptions,
     Disclosure of evidence.



     Indictments found and returned in the Superior Court
Department on November 9, 2006.

     A motion to withdraw a guilty plea, filed on October 2,
2012, and supplemented on March 20, 2014, was heard by Paul A.
Chernoff, J., special judicial magistrate, and an order
affirming the proposed order of the special judicial magistrate
was entered by Frank M. Gaziano, J.

     The Supreme Judicial Court granted an application for
direct appellate review.


     Patrick Levin, Committee for Public Counsel Services, for
the defendant.
                                                                       2


     Laurie Yeshulas, Assistant District Attorney (Lisa J.
Jacobs, Assistant District Attorney, with her) for the
Commonwealth.


     SPINA, J.   The present case is the most recent in a series

of cases concerning the egregious misconduct of Annie Dookhan, a

chemist who was employed in the forensic drug laboratory of the

William A. Hinton State Laboratory Institute (Hinton drug lab)

from 2003 until 2012.      On January 23, 2007, the defendant,

Admilson Resende, pleaded guilty on indictments charging

distribution of a class B controlled substance (cocaine), G. L.

c. 94C, § 32A (c) (five counts); violation of the controlled

substances laws in proximity to a school or park, G. L. c. 94C,

§ 32J (three counts); and possession of a class B controlled

substance (cocaine) with intent to distribute, G. L. c. 94C,

§ 32A (c) (one count). 1    He completed service of his sentences. 2

On October 2, 2012, the defendant filed in the Superior Court a

motion to withdraw his guilty pleas pursuant to Mass. R. Crim.

     1
       An indictment charging unlawful possession of a class D
controlled substance (marijuana), G. L. c. 94C, § 34, as amended
through St. 1996, c. 271, § 1, was placed on file.
     2
       With respect to the indictments charging distribution of
cocaine and possession of cocaine with intent to distribute, the
defendant was sentenced to concurrent terms of a mandatory
minimum sentence of one year in a house of correction. G. L.
c. 94C, § 32A (c), as amended through St. 1991, c. 391. With
respect to the school or park zone charges, the defendant was
sentenced to concurrent terms of a mandatory minimum sentence of
two years in a house of correction, to commence on and after the
completion of his sentences for the underlying drug crimes.
G. L. c. 94C, § 32J, as amended through St. 1998, c. 194, § 146.
                                                                      3


P. 30, as appearing in 435 Mass. 1501 (2001), based on Dookhan's

malfeasance.

       Prior to the issuance of a ruling on the defendant's

motion, this court decided Commonwealth v. Scott, 467 Mass. 336

(2014), in which we articulated, in reliance on Ferrara v.

United States, 456 F.3d 278, 290-297 (1st Cir. 2006), a two-

prong framework for analyzing a defendant's motion to withdraw a

guilty plea under rule 30 (b) in a case involving the misconduct

of Dookhan at the Hinton drug lab.     Scott, supra at 346-358.

Under the first prong of the analysis, a defendant must show

egregious misconduct by the government that preceded the entry

of the defendant's guilty plea and that occurred in the

defendant's case.    Id. at 347-354.   We recognized that, given

the breadth and duration of Dookhan's malfeasance, it might be

impossible for a defendant to show the required nexus between

government misconduct and the defendant's own case.     Id. at 351-

352.    Consequently, we established a special evidentiary rule

whereby a defendant seeking to vacate a guilty plea under rule

30 (b) as a result of the revelation of Dookhan's misconduct,

and proffering a certificate of drug analysis (drug certificate)

from the defendant's case signed by Dookhan on the line labeled

"Assistant Analyst," would be entitled to "a conclusive

presumption that egregious government misconduct occurred in the

defendant's case."    Id. at 352.   Application of this conclusive
                                                                       4


presumption in a particular case meant that a defendant's

evidentiary burden to establish each element of the first prong

of the Ferrara-Scott framework was satisfied.    Id. at 353-354.

The defendant then had the burden under the second prong of the

analysis of particularizing Dookhan's misconduct to his or her

decision to tender a guilty plea.   Id. at 354-355.   That is to

say, the defendant had to "demonstrate a reasonable probability

that he [or she] would not have pleaded guilty had he [or she]

known of Dookhan's misconduct."   Id. at 355.   A successful

showing on this second prong of the Ferrara-Scott framework

would warrant an order granting the defendant's motion to

withdraw a guilty plea.

     In light of our decision in Scott, as well as new evidence

concerning the Hinton drug lab's analyses of the samples in his

case, 3 the defendant filed supplemental pleadings on March 20,

2014, in support of his motion to withdraw his guilty pleas.      He

pointed out that Dookhan had set up and operated the gas

chromatography-mass spectrometry (GC-MS) machine for three out

     3
       On April 1, 2013, defense counsel filed a motion in the
Superior Court for the production of documentation from the
forensic drug laboratory of the William A. Hinton State
Laboratory Institute (Hinton drug lab) that supported the
results set forth on each certificate of drug analysis (drug
certificate) in the defendant's case. Counsel sought, in
particular, the reviewable data produced by the gas
chromatography-mass spectrometry (GC-MS) machine that had
performed the drug analyses. The motion was allowed, and the
office of the Inspector General produced the requested
documentation.
                                                                     5


of the seven samples in his case (although her name did not

appear on those drug certificates), and that she had been the

confirmatory chemist for a fourth sample.    As a consequence, the

defendant asserted that, with respect to these four samples, he

was entitled to the conclusive presumption articulated in Scott,

467 Mass. at 352, that egregious government misconduct occurred

in his case.    He further argued that he would not have pleaded

guilty had he known of Dookhan's misconduct at the time of his

pleas.

     Following an evidentiary hearing, a special magistrate

appointed by the Chief Justice of the Superior Court Department

of the Trial Court pursuant to Mass. R. Crim. P. 47, 378 Mass.

923 (1979), denied the defendant's motion to withdraw his guilty

pleas.    See Commonwealth v. Charles, 466 Mass. 63, 89-90 (2013)

(describing authority of special magistrate to conduct guilty

plea colloquies in Hinton drug lab sessions).    The defendant

appealed the special magistrate's proposed order dated May 12,

2014, to the Regional Administrative Justice of the Superior

Court, who denied the defendant's appeal and affirmed the

decision of the special magistrate.    See id. at 66, 90-91.   The

defendant filed a timely notice of appeal in the Appeals Court,

and we subsequently granted his application for direct appellate

review.    For the reasons that follow, we conclude that the

defendant was not entitled to the conclusive presumption that
                                                                     6


egregious government misconduct occurred in his case, and that

his motion to withdraw his guilty pleas was properly denied. 4

     1.    Background.   On four divers dates in August, 2006,

Detective Timothy Stanton of the Brockton police department

conducted "controlled buys" of what appeared to be cocaine from

the defendant.    Each purchase occurred in a similar manner.

Stanton would telephone a number that had been provided by the

defendant and would meet him (or, on the first occasion, a

female associate) at a designated location in the "Village"

section of Brockton.     Each of these locations was within 1,000

feet of an elementary school or a park.     Stanton would purchase

two "twenty" bags of an off-white rock-like substance from the

defendant for forty dollars.     Before and after several of these

controlled buys, the defendant was observed leaving and

reentering a multifamily home on North Montello Street.     Field

tests conducted on the substances indicated the presumptive

presence of cocaine.     Based on these controlled buys, Stanton

applied for and was granted a search warrant for the defendant's

residence on the first floor of the North Montello Street

address.




     4
       Although our recent decision in Commonwealth v. Resende,
474 Mass. 455 (2016), concerned the same defendant as in the
present case, the issues raised in the two cases are entirely
different.
                                                                    7


     On August 22, 2006, Stanton engaged in a fifth controlled

buy with the intention of executing the search warrant

immediately thereafter.   He telephoned the defendant, who

directed him to the corner of North Montello Street and King

Avenue and advised him that he would have one "forty" bag

instead of two "twenty" bags.   When Stanton arrived at the

meeting place, he telephoned the defendant and subsequently

observed him leaving the residence on North Montello Street.

Stanton gave the defendant two twenty dollar bills with

prerecorded serial numbers in exchange for a clear plastic bag

containing an off-white rock-like substance.   A team of police

officers then secured the defendant and took him into custody.

The defendant was advised of the Miranda rights and acknowledged

that he understood those rights.   Found on the defendant's

person were a Nextel cellular telephone (on which Stanton's

telephone call was still visible), three pieces of an off-white

rock-like substance wrapped in clear plastic, a bag containing

green vegetable matter, and two twenty dollar bills having the

prerecorded serial numbers.

     The substances recovered from the five controlled buys and

from the defendant's person were sent to the Hinton drug lab for

analysis.   Seven drug certificates were issued.   As relevant to

the present appeal, three of the drug certificates, stating that

the substances seized from the defendant contained cocaine as
                                                                    8


defined in G. L. c. 94C, § 31, were signed on the line labeled

"Assistant Analysts" by Daniela Frasca and Michael Lawler.

However, as will be explained in greater detail infra, Dookhan

was the so-called "setup operator" for the substances (samples

779099, 779110, and 779125) that were analyzed to generate these

certificates.    A fourth drug certificate, stating that the

substance (sample 810059) seized from the defendant contained

cocaine as defined in G. L. c. 94C, § 31, was signed on the line

labeled "Assistant Analysts" by Frasca and Dookhan. 5

     In 2012, Dookhan admitted to tampering with evidence at the

Hinton drug lab, failing to comply with quality control

measures, forging the initials of an evidence officer, and "dry

labbing." 6   See Scott, 467 Mass. at 339-340.   It appeared that

"the motive for her wrongdoing was in large part a desire to

increase her apparent productivity."    Id. at 341.   Following a

     5
       Two of the remaining drug certificates, stating that the
substances (samples 810300 and 810301) seized from the defendant
contained cocaine as defined in G. L. c. 94C, § 31, were signed
on the line labeled "Assistant Analysts" by Kate Corbett and
Della Saunders. The final drug certificate, stating that the
substance (sample 810302) seized from the defendant contained
marijuana as defined in G. L. c. 94C, § 31, was signed on the
line labeled "Assistant Analyst" by Saunders. Because there is
no evidence that Dookhan was involved in the analyses of the
substances for which these three drug certificates were
generated, we do not consider them further.
     6
       Dookhan's admission to "dry labbing" meant that "she would
group multiple samples together from various cases that looked
alike and then test only a few samples, but report the results
as if she had tested each sample individually." Commonwealth v.
Scott, 467 Mass. 336, 339 (2014).
                                                                    9


criminal investigation into Dookhan's misconduct, the Attorney

General's office indicted her on twenty-seven charges --

seventeen counts of tampering with evidence, eight counts of

obstruction of justice, one count of perjury, and one count of

falsely claiming to hold a degree from a college or university.

See id. at 337 & n.3.   On November 22, 2013, Dookhan pleaded

guilty to all of the charges.   See id.    She was sentenced to

from three years to five years in the State prison, followed by

a probationary term of two years.

     2.   Testing procedures at the Hinton drug lab.    At the

April 22, 2014, hearing before the special magistrate on the

defendant's motion to withdraw his guilty pleas, the parties

presented, among other evidence, a report from the office of the

Inspector General (report), dated March 4, 2014, describing its

comprehensive investigation of the operation and management of

the Hinton drug lab from 2002 to 2012. 7   In addition, the

defendant presented the testimony of Michael Lawler, the

confirmatory chemist for samples 779099, 779110, and 779125,

with respect to which Dookhan was the setup operator. 8   Lawler,


     7
       The report was issued one day before the release of our
opinion in Scott and greatly enhanced public understanding of
the details surrounding Dookhan's misconduct at the Hinton drug
lab.
     8
       On November 4, 2014, the defendant filed a motion to
reconstruct the testimony given by Lawler at the hearing on the
defendant's motion to withdraw his guilty pleas. Due to an
                                                                  10


whom the special magistrate found to be credible, described the

GC-MS machine, as well as the duties and responsibilities of a

primary chemist, a confirmatory chemist, and a setup operator.

     When a law enforcement agency brought a substance to the

Hinton drug lab for analysis, an evidence officer would accept

the substance and assign it a sample number, which would be

attached to the substance through all of the phases of the

testing process.   The evidence officer would create a drug

receipt, which included the sample number, and would give a copy

of the receipt to the law enforcement agency that had requested

the analysis.   Then, the evidence officer would generate a

control card 9 and place it, together with the substance, in a

manila envelope labeled with the sample number.   Eventually, the

substance would be assigned to a chemist for analysis.

     The special magistrate described the testing process used

by the Hinton drug lab as a "two-phase system," rather than a




equipment malfunction, a transcript of that hearing could not be
produced. The parties subsequently filed a joint statement
regarding their recollections of Lawler's testimony, and the
special magistrate accepted the statement.
     9
       The control card would list information about the sample,
including its number, its net weight, the identity of the
primary and confirmatory chemists assigned to the sample, and
the analytical results. The control card stayed with the sample
throughout the testing process.
                                                                      11


"two-chemist system." 10    During the preliminary phase, substances

submitted by law enforcement agencies for analysis were assigned

to a primary chemist.      That individual would be responsible for

weighing the samples and conducting preliminary bench tests,

which included color, microcrystalline, gas chromatography,

infrared spectroscopy, ultraviolet spectroscopy, macroscopic,

and microscopic tests.     The primary chemist would document the

test results and make preliminary determinations as to the

identities of the samples.     Then, the primary chemist would

prepare the samples for the confirmatory testing process by

making aliquots 11 for analysis by the GC-MS machine.    In

addition, the primary chemist would complete a GC-MS control

sheet, setting forth the date, the identity of the primary

chemist, the name of the submitting law enforcement agency, a

list of samples in numerical order, the chemist's preliminary

     10
       The special magistrate found that under a "two-chemist
system," the primary chemist conducted the preliminary bench
tests, and the confirmatory chemist received the samples for
analysis by the GC-MS machine, operated the GC-MS machine, and
confirmed the preliminary findings made by the primary chemist.
In contrast, under a "two-phase system," one chemist was
responsible for the preliminary testing phase, and one or two
different chemists were responsible for the confirmatory phase
(except in rare instances when a single chemist completed both
phases). When performing the confirmatory phase, one chemist
would receive the samples and operate the GC-MS machine, and a
different chemist would analyze the results generated by the GC-
MS machine.
     11
       An aliquot is a small portion of the sample that the
primary chemist places into a glass vial and dissolves with a
solvent.
                                                                   12


findings, and any comments that would be helpful to the

confirmatory chemist in the subsequent analysis.   Finally, the

primary chemist would take the GC-MS control sheet, the control

card, and the aliquots to the room where the GC-MS machines were

located (GC-MS room) so that the confirmatory phase of the

testing process could begin.

     With respect to the confirmatory testing process, the

Hinton drug lab generally followed the protocol recommended by

the Scientific Working Group for the Analysis of Seized Drugs,

which relied on use of a GC-MS machine.   The GC-MS room was

situated in the middle of the laboratory complex and was

accessible by only one door.   Each machine was a large, box-

shaped piece of equipment with a robotic arm that had a syringe

attached to the end of it.   Placed inside the GC-MS machine was

a carousel which could be loaded with 100 to 120 vials,

depending on the size of the machine.   When operational, the

carousel would move the vials toward the syringe which would

puncture the top of each vial to commence the testing process

for that sample.   After the contents of a vial were analyzed,

the GC-MS machine automatically purged the syringe by "spitting"

its contents into a waste receptacle and then putting the

syringe into a cleaning solution.

     The confirmatory phase involved three separate steps --

receipt of the samples in the GC-MS room, operation of the GC-MS
                                                                    13


machine, and analysis of the results from the GC-MS machine to

confirm the preliminary identification of the samples.    It was

common practice at the Hinton drug lab for the setup operator to

complete the first two steps, and for the confirmatory chemist,

who signed the drug certificates, to complete the last step. 12

Chemists were assigned to work as the setup operator for week-

long shifts.   Although the setup operator had some level of

autonomy because he or she was not directly supervised, a

supervisor usually was present in the GC-MS room.   On some

occasions, the setup operator would become the confirmatory

chemist and would analyze the results produced by the GC-MS

machine.   On other occasions, the GC-MS machine would run

overnight, so the setup operator might not be the chemist who

would interpret the results the following morning and sign the

drug certificates.

     At the beginning of the confirmatory phase, the setup

operator would receive the aliquots from the primary chemist and

verify that the number on each vial matched the sample numbers

on the accompanying GC-MS control sheet and control card.     The

setup operator would inspect the vials and document any

problems, including signs of contamination.   Then, he or she

     12
       According to the special magistrate's findings and the
report from the office of the Inspector General, chemists at the
Hinton drug lab did not consider it to be a requirement that one
chemist perform all three steps of the confirmatory phase of the
testing process.
                                                                     14


would place the aliquots, along with vials containing

standards, 13 blanks, 14 and a quality control standard mix, 15 on

the carousel of the GC-MS machine for analysis.     The setup

operator would complete a "sequence" or "batch" sheet, an

internal document that specified the order in which the various

vials were arranged on the carousel, and enter the information

from the sheet into the GC-MS machine.     The setup operator would

not open the aliquots.

     Before the aliquots could be analyzed, the setup operator

was required to confirm that the GC-MS machine was ready for

operation.   This involved "tuning" the GC-MS machine to ensure

that it was operating within acceptable parameters, ascertaining

that the GC-MS machine correctly identified the quality control

standard mix, and confirming that tests on the first few vials

     13
       A standard was a known controlled substance against which
the aliquots were compared. In the present case, the standard
was cocaine. The aliquots being analyzed were bracketed by
standards to ensure that the GC-MS machine was operating
properly at the beginning, middle, and end of the testing
sequence. If the setup operator noticed that the GC-MS machine
had not identified the standard correctly, the "run" of the
assorted vials would be terminated, and another run would be
prepared using a new standard.
     14
       Blanks typically consisted of the solvent that had been
used to dissolve the aliquots. They were inserted on the
carousel between the aliquots and the standards, and were used
to ensure that there was no contamination during the testing
process.
     15
       The quality control standard mix was a combination of
cocaine and codeine. It was used to ensure that the GC-MS
machine was operating properly.
                                                                    15


containing standards and blanks also correctly identified those

substances.     In addition, the setup operator was responsible for

other quality control measures, including ensuring that the

standards were not contaminated, emptying the waste receptacle,

lubricating the syringe, and replacing the injection seal, as

necessary. 16   If at any time the setup operator determined that

the GC-MS machine was not fit for operation, the operator would

terminate the "run" of a batch of vials and restart the analysis

process.

     The GC-MS machine would produce reviewable data that the

chemists referred to as "documentation."    Once the GC-MS machine

had completed its analysis of the aliquots, the confirmatory

chemist would check the placement of the vials against the

sequence sheet to ensure that they were tested in the correct

order.    The confirmatory chemist then would analyze the

documentation and identify each sample without using the primary

chemist's notes.    This identification would be added to the

front of the GC-MS control sheet and the control card.      A sample

would have to test positive in both the preliminary and

confirmatory phases in order to be conclusively identified as

the controlled substance at issue.    Finally, the primary and

confirmatory chemists would sign the drug certificates.     If


     16
       The location and purpose of the injection seal are
unclear from the record.
                                                                     16


there was an inconsistency between the identification made by

the primary chemist and that made by the confirmatory chemist,

the samples would be returned to the primary chemist for further

analysis or for the preparation of new aliquots.

     3.    Testing in the defendant's case.   As to samples 779099,

779110, and 779125, Lawler testified that Daniela Frasca was the

primary chemist, Dookhan was the setup operator, and he was the

confirmatory chemist.    Frasca conducted the bench tests,

prepared the aliquots for analysis by the GC-MS machine, and

preliminarily identified the three samples as cocaine.     Dookhan

then placed the assorted vials on the carousel of the GC-MS

machine on Friday, October 6, 2006, and entered the sequence of

their arrangement into the machine.    She initiated the analysis

process that morning, it continued throughout the night, and it

was finished the following morning, Saturday, October 7.     Lawler

testified that Dookhan would have been responsible for

performing any necessary quality control measures, and for

ensuring that the GC-MS machine was operating properly prior to

the run.    Once the analysis was completed on Saturday morning,

Lawler reviewed the performance of and documentation from the

GC-MS machine.    He testified that he would have checked the GC-

MS machine and would have examined the placement of the vials

before he removed them from the carousel.     Based on his review

of the documentation, Lawler confirmed that samples 779099,
                                                                     17


779110, and 779125 contained cocaine, and he signed the drug

certificates. 17

     Lawler testified that although he had some concerns about

Dookhan based on her productivity as a primary chemist, he did

not have similar concerns regarding her work in the GC-MS room.

Lawler stated that confirmatory testing on the GC-MS machine was

"very static," meaning that it was not possible to increase or

accelerate the process, and that it did not involve any

"creativity."      When asked how a "rogue" person could influence

the results of the GC-MS machine, Lawler testified that he did

not see how it could be done without detection.

     4.   Decision of the special magistrate.    In a thorough and

well-reasoned memorandum of decision denying the defendant's

motion to withdraw his guilty pleas, the special magistrate

pointed out that Scott does not address whether the conclusive

presumption of egregious government misconduct is available to a

defendant in a case where Dookhan merely was the setup operator

and did not sign the drug certificates.     The special magistrate

found that the roles of setup operator and confirmatory chemist,

while overlapping, were not so closely analogous or

interchangeable that they should be treated as one, and that the

language in Scott clearly limits the conclusive presumption to

     17
       With respect to sample 810059, Dookhan signed the drug
certificate on the line labeled "Assistant Analysts," certifying
that the sample contained cocaine.
                                                                   18


those cases where Dookhan was the primary or confirmatory

chemist.   Accordingly, he declined to expand the scope of Scott

such that the defendant would be entitled to a conclusive

presumption that egregious government misconduct occurred with

respect to the analyses of samples 779099, 779110, and 779125.

     The special magistrate then considered whether, absent the

conclusive presumption, the defendant nonetheless had

demonstrated that Dookhan, while acting as the setup operator,

had engaged in "particularly pernicious" misconduct, and that

such misconduct was material to the defendant's decision to

plead guilty.   See Scott, 467 Mass. at 346-348, 354-355, citing

Ferrara, 456 F.3d at 290, 291.   The special magistrate found

that there was no evidence that Dookhan had acted with

purposeful malfeasance while serving as the setup operator for

samples 779099, 779110, and 779125.   To the contrary, he

continued, the evidence indicated that Dookhan had performed her

duties as would have been expected.   That being the case, the

special magistrate concluded that the defendant had failed to

satisfy his burden of proof with respect to the first prong of

the Ferrara-Scott framework.   Turning to the second prong of the

framework, the special magistrate also concluded that the

defendant had not demonstrated a reasonable probability that he

would not have pleaded guilty had he known of Dookhan's

misconduct.   He found that the factual bases for the defendant's
                                                                    19


guilty pleas were not substantially weakened by Dookhan's

purported misconduct in this case, and that the defendant's

sentences after pleading guilty were considerably more favorable

than the sentences that could have been imposed if he had

proceeded to trial.

     Finally, with respect to sample 810059, the special

magistrate stated that because Dookhan was the confirmatory

chemist, the defendant was entitled to the conclusive

presumption articulated in Scott that egregious government

misconduct occurred with respect to the analysis of this

particular sample.    However, he concluded that, for essentially

the same reasons he already had articulated, the defendant had

failed to satisfy his burden of proof under the second prong of

the Ferrara-Scott framework.    Accordingly, the special

magistrate denied the defendant's motion to withdraw his guilty

pleas.

     5.   Standard of review.   A motion to withdraw a guilty plea

is treated as a motion for a new trial pursuant to Mass. R.

Crim. P. 30 (b).    Commonwealth v. Furr, 454 Mass. 101, 106

(2009).   "Under Mass. R. Crim. P. 30 (b), a judge may grant a

motion for a new trial any time it appears that justice may not

have been done.    A motion for a new trial is thus committed to

the sound discretion of the judge."    Scott, 467 Mass. at 344.

We review the allowance or denial of a motion to withdraw a
                                                                    20


guilty plea to determine whether the judge abused that

discretion or committed a significant error of law.   Id.      We

accept the judge's findings of fact if they are supported by the

evidence because the judge who heard the witnesses testify is

the "final arbiter [on] matters of credibility."   Id., quoting

Commonwealth v. Schand, 420 Mass. 783, 787 (1995).

     6.   Egregious misconduct by the government in the

defendant's case.   The defendant first contends that, although

Dookhan did not sign the drug certificates pertaining to samples

779099, 779110, and 779125, she nonetheless effectively acted as

a confirmatory chemist for those samples because she tuned the

GC-MS machine, verified that it was functioning properly, placed

the vials on the carousel, and initiated the analysis process.

The defendant points out that Dookhan's admitted misconduct

while serving as a confirmatory chemist included the failure to

verify the proper functioning of a GC-MS machine and the

falsification of reports to hide her wrongdoing.   See Scott, 467

Mass. at 339-341, 353 n.9.   In light of this malfeasance, the

defendant argues that he was entitled to the conclusive

presumption articulated in Scott, 467 Mass. at 352, that

egregious government misconduct occurred in his case.     We

disagree.

     We stated in Scott, supra at 339-341, 353 n.9, that Dookhan

appeared to have engaged in misconduct during the confirmatory
                                                                   21


phase of the analysis process at the Hinton drug lab.   However,

the present case is not one in which Dookhan was performing the

dual roles of setup operator and confirmatory chemist with

respect to samples 779099, 779110, and 779125.   Contrary to the

defendant's assertions, Dookhan's work as the setup operator did

not involve the "testing" of drugs.   Testing was performed first

by the primary chemist (Frasca), who completed bench tests and

made a preliminary identification of each sample based on her

subjective interpretation of the results, and then by the GC-MS

machine, which produced documentation that was reviewed and

interpreted by the confirmatory chemist (Lawler).   Notably,

Dookhan did not prepare the aliquots for analysis by the GC-MS

machine because that task was the responsibility of Frasca.

Dookhan's role was simply to receive the aliquots, prepare the

GC-MS machine, and initiate the analysis process.   Once the

analysis process had been completed, Lawler checked the GC-MS

machine, verified the proper placement of the vials on the

carousel, and reviewed the documentation.   If there had been any

inconsistency between the identification made by Frasca and that

made by Lawler, the samples would have been returned to Frasca

for further analysis or for the preparation of new aliquots.    In

the opinion of Lawler, whom the special magistrate found to be

credible, tampering with the GC-MS machine would have been

detectable.
                                                                   22


     Significantly, the office of the Inspector General found no

evidence that Dookhan tampered with drug samples that were

assigned to other chemists, such as Frasca and Lawler in the

present case.   When Dookhan tampered with her own samples, it

appeared that she was motivated, in large part, by her desire to

increase her apparent productivity.      See Scott, 467 Mass. at

341, 352.   Given that there was no way to increase or accelerate

the analysis process on a GC-MS machine, Dookhan would have had

no reason to tinker with its operation while serving as the

setup operator.   Any such tinkering would not have enhanced her

productivity.   Indeed, based on its comprehensive investigation

of the Hinton drug lab from 2002 to 2012, the office of the

Inspector General did not suggest treating with increased

suspicion those cases where Dookhan served as the setup

operator.   We conclude that the special magistrate did not abuse

his discretion or otherwise err in determining that the

defendant was not entitled to the conclusive presumption

articulated in Scott, supra at 352, that egregious government

misconduct occurred in his case with respect to the analyses of

samples 779099, 779110, and 779125. 18



     18
       Given that Dookhan signed the drug certificate for sample
810059 on the line labeled "Assistant Analysts," the special
magistrate properly concluded that the defendant was entitled to
the conclusive presumption that egregious government misconduct
occurred with respect to the analysis of this particular sample.
                                                                     23


     Absent this conclusive presumption, a defendant who moves

to withdraw his guilty pleas has the evidentiary burden of

establishing, as an initial matter, each element of the first

prong of the Ferrara-Scott framework.    See Ferrara, 456 F.3d at

290; Scott, 467 Mass. at 346-354.    Here, the defendant was

required to show that Dookhan engaged in "egregiously

impermissible conduct" in his case, and that such misconduct

preceded the entry of his guilty pleas. 19   Ferrara, supra.   See

Scott, supra.    Based on the report, the timing and the scope of

Dookhan's misconduct during the confirmatory phase of the

analysis process at the Hinton drug lab do not suggest that she

engaged in malfeasance with respect to samples 779099, 779110,

and 779125, which were analyzed in October, 2006.

     First, the report found that around March, 2011, chemist

Kate Corbett reported to the supervisor of the GC-MS room that

Dookhan had forged her initials on a batch sheet, falsely

indicating that Corbett had been the operator of the GC-MS

machine for the particular run of samples indicated on the

sheet.    Apart from the fact that this incident occurred nearly

four and one-half years after the defendant's samples were

analyzed, there was no evidence to suggest that Dookhan had


     19
       It is well established that Dookhan's work at the Hinton
drug lab, including her service as the setup operator for
samples 779099, 779110, and 779125, was conduct "by the
government." Scott, 467 Mass. at 348-350.
                                                                     24


tampered with the actual operation of the GC-MS machine,

notwithstanding her forgery of Corbett's initials on the batch

sheet.     Next, the report found that between May 10, 2011, and

May 14, 2011, Dookhan falsified four days of reports pertaining

to the quality control standard mix runs on the GC-MS machine.

See note 15, supra.     Dookhan completed these reports as if the

GC-MS machine had performed satisfactorily, when it had not, and

then she signed the reports as the "quality control reviewer,"

thereby approving her own falsified test results. 20   After

discovering this misconduct, the office of the Inspector General

reviewed 3,930 quality control standard mix results from 2005 to

2012.     It did not find any additional falsified reports or

evidence of other wrongdoing with respect to the quality control

standard mixes.     Finally, the report found that in June, 2011,

Dookhan forged the initials of chemist Nicole Medina on a so-

called "tune report."     During the course of its comprehensive

investigation, the OIG reviewed tune reports from 2009 to 2012.

It did not find any reports indicating that the GC-MS machines

were operating outside acceptable parameters.     We conclude that

     20
       According to the report, the job of the "quality control
reviewer" was "to collect the quality control record from the
chemists and various areas of the lab, ensure that the chemists
had filled in the records, sign them, and present them" to the
"quality assurance reviewers." The signature of the "quality
control reviewer" documented that "the reviewer had looked at a
list of checkmarks on a completed form created by a chemist
indicating he or she had performed one of the necessary quality
control tasks."
                                                                    25


the defendant did not establish that Dookhan engaged in

egregious misconduct while serving as the setup operator for

samples 779099, 779110, and 779125.    Accordingly, the special

magistrate properly determined that the defendant could not

withdraw his guilty pleas where he failed to satisfy each

element of the first prong of the Ferrara-Scott framework.

     As discussed, the analysis of a defendant's motion to

withdraw a guilty plea under Mass. R. Crim. P. 30 (b) in a case

involving the misconduct of Dookhan at the Hinton drug lab

proceeds under a two-prong framework.    See Scott, 467 Mass. at

346-358, citing Ferrara, 456 F.3d at 290, 291.    Given our

conclusion that the defendant here has failed to satisfy the

first prong of the framework with respect to the testing of

samples 779099, 779110, and 779125, we need not further consider

whether, under the second prong, the defendant demonstrated "a

reasonable probability that he would not have pleaded guilty had

he known of Dookhan's misconduct."    Scott, supra at 355.    See

Ferrara, supra at 290, 294.   However, the second prong is

relevant with respect to sample 810059 because the drug

certificate pertaining to that one sample, stating that it

contained cocaine as defined in G. L. c. 94C, § 31, was signed

on the line labeled "Assistant Analysts" by Frasca and Dookhan.

As to that one sample, the defendant was deemed to have

satisfied each element of the first prong of the Ferrara-Scott
                                                                    26


framework.   See Scott, supra at 353-354.   We therefore proceed

to consider the second prong as it relates to sample 810059. 21

     7.   Material influence on the defendant's decision to plead

guilty.   Under the second prong of the Ferrara-Scott framework,

the defendant had the burden of particularizing "Dookhan's

misconduct to his decision to tender a guilty plea."    See Scott,

467 Mass. at 354.   That is to say, the defendant had to

demonstrate, based on a totality of the circumstances, "a

reasonable probability that he would not have pleaded guilty had

he known of Dookhan's misconduct."   Id. at 355.   In reliance on

Ferrara, 456 F.3d at 294, this court identified in Scott a

number of factors that could be relevant to a defendant's

showing under this second prong, including "(1) whether evidence

of the government misconduct could have detracted from the

factual basis used to support the guilty plea, (2) whether the

evidence could have been used to impeach a witness whose

credibility may have been outcome-determinative, (3) whether the

evidence was cumulative of other evidence already in the

defendant's possession, (4) whether the evidence would have

influenced counsel's recommendation as to whether to accept a

particular plea offer, and (5) whether the value of the evidence

was outweighed by the benefits of entering into the plea

     21
       Sample 810059 pertained to indictments charging
distribution of cocaine and violation of the controlled
substances laws in proximity to a school.
                                                                      27


agreement."    Scott, supra at 355-356.   Additional factors for

consideration under the second prong might include, but are not

limited to, "whether the defendant was indicted on additional

charges," id. at 357, as well as "whether the defendant had a

substantial ground of defense that would have been pursued at

trial," id. at 356, and whether other special circumstances,

such as collateral immigration consequences arising from

conviction of a particular crime, were present.     Id. at 356 &

n.13, citing Commonwealth v. Clarke, 460 Mass. 30, 47-48 (2011).

     "Ultimately, a defendant's decision to tender a guilty plea

is a unique, individualized decision, and the relevant factors

and their relative weight will differ from one case to the

next."    Scott, 467 Mass. at 356.   We emphasized in Scott that

"the full context of the defendant's decision to enter a plea

agreement will dictate the assessment of his claim that

knowledge of Dookhan's misconduct would have influenced the

defendant's decision to plead guilty."     Id. at 357.   "Because a

multiplicity of factors may influence a defendant's decision to

enter a guilty plea, a court attempting to answer this question

must use a wide-angled lens."    Ferrara, 456 F.3d at 294.

     The defendant contends that the special magistrate erred in

concluding that knowledge of Dookhan's misconduct likely would

not have been material to the defendant's decision to plead

guilty.    The defendant points out that he did not have a prior
                                                                    28


criminal record, and he contends that he pleaded guilty only

because he believed that he had no viable trial strategy in

light of the Commonwealth's presentation of the drug

certificates.   The defendant emphasizes that there was no plea

bargain in this case because not only did the Commonwealth

refuse to dismiss any of the charges against him, but the

prosecutor also urged the judge to impose an aggregate sentence

of from four to six years in State prison, rather than three

years in a house of correction, as the defendant requested.    In

the defendant's view, he did not receive a substantial benefit

from pleading guilty.   Had he known of Dookhan's malfeasance,

the defendant continues, he would have had "nothing to lose but

everything to gain" by proceeding to trial and challenging the

reliability of her work at the Hinton drug lab.    We disagree.

     Apart from the drug certificates, the evidence against the

defendant was strong.   Stanton conducted five controlled buys,

each of which involved a hand-to-hand exchange of cash for two

"twenty" bags or one "forty" bag of an off-white rock-like

substance.   Not only could a rational jury have inferred that

Stanton received what he had requested from the defendant, but

field tests conducted on the substances indicated the

presumptive presence of cocaine. 22   See Commonwealth v. Marte, 84


     22
       Although it does not appear that field tests were
performed on the substances recovered from the defendant when he
                                                                   29


Mass. App. Ct. 136, 139-142 (2013) (presumptively positive field

tests having requisite foundation, together with other

corroborative circumstantial evidence, may carry persuasive

weight in identifying substances).   See also Commonwealth v.

Dawson, 399 Mass. 465, 467 (1987) ("Proof that a substance is a

particular drug need not be made by chemical analysis and may be

made by circumstantial evidence").   Notwithstanding the fact

that all but one of the drug certificates were signed by

chemists other than Dookhan, evidence of her misconduct would

not have detracted from the factual bases supporting the

defendant's guilty pleas.   Furthermore, apart from Dookhan's

malfeasance, there is no evidence that the defendant had a

substantial ground of defense that he would have pursued at

trial.

     Contrary to the defendant's argument, he did receive a

significant benefit from pleading guilty instead of proceeding

to trial.   With respect to six counts of distribution of cocaine

and possession of cocaine with intent to distribute, the judge

sentenced the defendant to concurrent terms of one year in a

house of correction.   Had the defendant gone to trial, he could



was taken into custody on August 22, 2006, the drug certificates
pertaining to those substances, stating that they contained
cocaine, were signed on the line labeled "Assistant Analysts" by
Kate Corbett and Della Saunders, and there is no evidence that
Dookhan was the setup operator for the analyses of those
substances.
                                                                    30


have been sentenced to from two and one-half years to ten years

in State prison, or from one year to two and one-half years in a

house of correction, on each count.    G. L. c. 94C, § 32A (c), as

amended through St. 1991, c. 391.    With respect to three counts

of violating the controlled substances laws in proximity to a

school or park, the judge sentenced the defendant to concurrent

terms of two years in a house of correction, to commence on and

after the completion of his sentences for the underlying drug

crimes.   Had the defendant gone to trial, he could have been

sentenced to from two and one-half years to fifteen years in

State prison, or from two years to two and one-half years in a

house of correction, from and after his sentences on the

underlying drug crimes, on each count.    G. L. c. 94C, § 32J, as

amended through St. 1998, c. 194, § 146.    In addition, with

respect to the marijuana charge, which was placed on file, the

defendant could have been sentenced to six months in a house of

correction.    G. L. c. 94C, § 34, as amended through St. 1996,

c. 271, § 1.    Regardless of the fact that the defendant did not

have a prior criminal record, his decision to plead guilty

resulted in the imposition of a far more lenient aggregate

sentence than the judge could have imposed following the

defendant's likely convictions after trial, given the strength

of the Commonwealth's evidence.    See Commonwealth v. Mills, 436

Mass. 387, 400 n.9 (2002) (judge may consider defendant's
                                                                   31


willingness to admit guilt as factor in more lenient

sentencing).   We conclude that the special magistrate did not

abuse his discretion or otherwise err in determining that the

defendant had failed to satisfy his burden of demonstrating a

reasonable probability that he would not have pleaded guilty had

he known of Dookhan's misconduct.

     8.   Conclusion.   The order denying the defendant's motion

to withdraw his guilty pleas is affirmed.

                                     So ordered.
