HAS THE MOST COMMON MARIJUANA TEST RESULTED IN TENS OF THOUSANDS OF
WRONGFUL CONVICTIONS?

More Than 800,000 People Are Arrested on Marijuana Charges Each Year
in the United States, Many on the Basis of an Error-Prone Test

Raised in Montana and a resident of Alaska for 18 years, Robin Rae
Brown, 48, always made time to explore in the wilderness. On March 20,
2009, she parked her pickup truck outside Weston, Florida, and hiked
off the beaten path along a remote canal and into the woods to bird
watch and commune with nature. "I saw a bobcat and an osprey," she
recalls. "I stopped once in a nice spot beneath a tree, sat down and
gave prayers of thanksgiving to God." For that purpose, Robin had
packed a clay bowl and a "smudge stick," a stalk-like bundle of sage,
sweet grass, and lavender that she had bought at an airport gift shop
in Albuquerque, New Mexico. Under the tree, she lit the end of the
smudge stick and nestled it inside the bowl. She waved the smoke up
toward her heart and over her head and prayed.

Spiritual people from many cultures, including Native Americans,
consider smoke to be sacred, she told me, and believe that it can
carry their prayers to the heavens.

As darkness approached, she returned to her pickup truck to find
Broward County's Deputy Sheriff Dominic Raimondi and Florida Fish and
Wildlife's Lieutenant David Bingham looking inside the cab. The two
men asked what she was doing and when she said she had been bird
watching, Bingham asked whether she had binoculars. As she opened her
knapsack, Officer Raimondi spotted her incense and asked if he could
see it. He took the bowl and incense, asking whether it was marijuana.
"No," she recalls saying. "It's my smudge, which is a blend of sage,
sweet grass, and lavender." "Smells like marijuana to me," said
Raimondi, who admitted he had never heard of a smudge stick.

He then ordered Robin to stand by her truck, while he took the incense
back to his car and conducted a common field test, known as a
Duquenois-Levine, or D-L, test. The result was positive for marijuana.

Robin protested, telling them the smudge was available for purchase
online for about $7 and gave them the name of a Web site that sold it
- -- information Officer Bingham used his laptop to verify.

But the men still searched her truck.

After an hour and a half they finally allowed Robin to go home and
told her that if a lab test confirmed the field test results, a
warrant would be issued for her arrest.

Exactly 90 days later, Robin was arrested at the spa in Weston,
Florida where she has worked as a massage therapist for three years.

She was handcuffed in front of clients and co-workers, and charged
with felony possession of marijuana.

She was brought to a local police precinct in the town of Davie where
she was booked and held for three hours.

Unable to post the $1,000 bail because she was not allowed to call her
boyfriend Michael, she was transferred to the Women's Correctional
Facility in Pompano Beach. At no time was she read her rights.

Five hours after her arrest, she was finally allowed a brief phone
call and left a message for Michael to post her bail. At the jail, a
female officer came in and told Robin to take off all her clothes.

She had already been searched at the precinct station and had her
shoes, socks and bra confiscated. "I'm on my period," she said. "I
don't care," said the officer, who ordered her to pull her underwear
down to her ankles, squat over the floor drain and cough.

The following morning at 4:30 a.m. she was released onto the streets
of Pompano Beach with no idea where she was.

The next day, Robin found a lab and submitted to voluntary hair and
urine tests.

These came back clean.

She had previously worked for 16 years as a transportation systems
specialist with the Federal Aviation Administration, a job that
required airport security clearances, so drug tests were nothing new
to her. During those years, she was frequently required to pass random
drug and alcohol tests.

She later learned that her incense had never been subjected to a
confirmatory lab test. She had been arrested and jailed solely on the
basis of her positive D-L test results.

The Preferred Test for Marijuana

The Duquenois test was developed in the late 1930s by a French
pharmacist, Pierre Duquenois, while he was working for the United
Nations division of narcotics.

In 1950, he completed a study for the UN which claimed that his test
was "very specific" for marijuana; it was adopted by the UN and crime
labs around the world as the preferred test for marijuana.

After undergoing several modifications, including the use of
chloroform, the test became known as the Duquenois-Levine test, and
became widely popular. Though scientists would show in the 1960s and
1970s that the D-L test was nonspecific, meaning it rendered false
positives, it remains today the most commonly used test for marijuana
- -- used in many of the 800,000 marijuana arrests that take place each
year.

The test is a simple chemical color reagent test, easy to perform but
difficult to interpret.

To administer the test, a police officer simply has to break a seal on
a tiny micropipette of chemicals, and insert a particle of the
suspected substance; if the chemicals turn purple, this indicates the
possibility of marijuana.

But the color variations can be subtle, and readings can vary by
examiner.

The field test kits are produced by a variety of manufacturers, the
most popular brands being NIK and ODV. Literature about the D-L from
NIK's makers states that it is only a "screening" test that "may or
may not yield a valid result" and may produce "false positive
results." Yet, since at least 1990, arresting officers, with the
support of prosecutors, have regularly bypassed lab analysts and have
purported to identify marijuana at hearings and trials only on the
basis of visual inspection and the nonspecific D-L field test. And the
manufacturers have taken note.

In 1998, ODV reported in its newsletter with seeming satisfaction that
a growing number of police departments were using its D-L field test,
marketed as the NarcoPouch, as "their sole method of testing and
identifying Marihuana [sic]... To have Officers properly trained in
identifying Marijuana and taking the Crime Lab out of the loop is a
tremendous cost saving venture for the State...and gives the individual
Officers testing the material a greater sense of satisfaction in
completing their own cases" (emphasis added). NIK, too, argued that
depending exclusively on D-L field tests saves time and money. "Crime
laboratories are so busy that drug tests take too long," NIK states on
its website. "With the cooperation of the Prosecuting Attorney, many
police agencies have turned to presumptive drug testing.

If the results indicate that an illegal substance is present, criminal
charges may be filed.

In June 2006, the Virginia legislature went so far as to pass
"emergency regulations" permitting law-enforcement officers to testify
at trial for simple possession of marijuana cases solely on the basis
of a D-L field test. Prior to these regulations, officers had to send
suspected material to an approved lab for testing.

Nothing in the new legislation specified that the field tests used had
to be specific, or even accurate. Frederic Whitehurst, a North
Carolina-based defense attorney and former FBI special agent with a
doctorate in chemistry, considers the law to be an unconstitutional
usurpation of the authority of the courts to determine what test
results can be admitted as valid evidence.

The trend toward police officers using the D-L as a confirmatory test
has been encouraged by the National Institute of Justice, an agency of
the Department of Justice which has funded programs to transform
police officers into court experts, based on their use of these faulty
field tests. One such ongoing program for the Utah police claims to
offer, in four days, "the necessary training" to positively identify
marijuana, which would allow officers to serve as "expert witnesses in
the courtroom setting." The program briefly covers the "botany,
chemistry and analysis of marijuana preparations," after which police
officers, including street detectives and crime scene lab personnel,
"will assume responsibility for all of their agency's marijuana
submissions." By the end of 2005, such submissions became the
exclusive provenance of the Utah officers who had attended the
training, and suspected marijuana samples were no longer accepted at
the state lab for processing.

In 2009, the Georgia Bureau of Investigation trained more than 1,600
police officers in the use of the D-L test, resulting in a 98 percent
reduction in the use of marijuana lab tests.

This troubling program garnered the bureau a 2009 Vollmer Excellence
in Forensic Science Award by the International Association of Chiefs
of Police.

Test 'Should Never Be Relied Upon'

Despite its widespread use, as early as the 1960s, the D-L test had
been proven incapable of definitively identifying the presence of
marijuana in a seized substance.

A 1968 article in the Chemistry and Pharmacy Bulletin of Japan
reported that the D-L tests "lack in adequate specificity." In 1969,
M. J. de Faubert Maunder, a chemist in the Ministry of Technology, a
UK government agency, documented the unreliability of the D-L test in
an article in the Bulletin on Narcotics, noting that test results
depended heavily on the subjective judgment of the analyst -- and thus
could easily vary dramatically from lab to lab. "[A] positive test is
not recorded until this colour has been identified," he wrote, "and
because it is almost impossible to describe in absolute terms it is
best recognised by experience." Moreover, he reported finding
twenty-five plant substances that would produce a D-L test result
barely distinguishable from that of Cannabis and cautioned that the
D-L test "should never be relied upon as the only positive evidence."

Several articles in the Journal of Forensic Sciences further disproved
any claims that the test could specifically identify marijuana.

A 1969 study in the journal reported false positive results from "a
variety of vegetable extracts." A 1972 study found that the D-L test
would test positive for many commonly occurring plant substances known
as resorcinols, which are found in over-the-counter medicines.

For instance, Sucrets lozenges tested positive for
marijuana.

This study concluded that the D-L test is useful only as a "screen"
test and was not sufficiently selective to be relied upon for
"identification." Still another study, in 1974, showed that 12 of 40
plant oils and extracts studied gave positive D-L test results.

In 1975, Dr. Marc Kurzman at the University of Minnesota, in
collaboration with fourteen other scientists, published a study in The
Journal of Criminal Defense that concluded: "The microscopic and
chemical screening tests presently used in marijuana analysis are not
specific even in combination for 'marijuana' defined in any way." In
the 35 years since that study was published, no one has ever refuted
this finding.

Indeed, recent research has confirmed Kurzman's findings.

In 2008, Whitehurst, the chemist and former FBI agent, substantiated
Kurzman's findings in an article in the Texas Tech Law Review. That
same year, Dr. Omar Bagasra, director of the South Carolina Center for
Biotechnology, conducted experiments in his lab also demonstrating
that the D-L test is nonspecific and renders false positives.

Bagasra, too, has impeccable credentials -- he's a leading pathologist
and a board-certified forensic examiner.

A number of high courts have been persuaded by this evidence, and have
found that the D-L test does not prove the presence of marijuana in a
seized substance.

In 1973, the Supreme Court of Wisconsin ruled that the D-L test
"standing alone is not sufficient to meet the burden of proving the
identity of the substance beyond a reasonable doubt." The court
specifically noted that the D-L field tests used in this marijuana
possession case "are not exclusive or specific for marijuana."

Similarly, in 1979, a trial judge in North Carolina blocked the
marijuana conviction of Richard Tate, which was to be based on
positive D-L test results.

In this case, too, the trial judge found that the D-L test was "not
specific for marijuana" and had "no scientific acceptance as a
reliable and accurate means of identifying the controlled substance
marijuana." On that basis, the judge allowed the defendant to suppress
the use of the test results as evidence.

This finding was upheld by the North Carolina Supreme Court, which
found that D-L test "was not scientifically acceptable because it was
not specific for marijuana" and thus "the test results were properly
suppressed."

Also in 1979, the U.S. Supreme Court in Jackson v. Virginia ruled that
the results of nonspecific tests could not be the basis for
prosecution or conviction. In other words, if the only evidence is a
positive D-L test, then the case must be dismissed.

As noted, even the test's manufacturers do not claim that their
product can definitively identify marijuana.

The literature accompanying NIK's NarcoPouch 908 cautions, "The
results of a single test may or may not yield a valid result... There is
no existing chemical reagent system, adaptable to field use, that will
completely eliminate the occurrence of an occasional invalid test
results [sic]. A complete forensic laboratory would be required to
qualitatively identify an unknown suspect substance."

Shoddy Science

Shoddy science, though, has muddied the waters.

Several studies claim, falsely, to have validated the specificity of
the D-L test. For instance, a seemingly authoritative 2000 study
funded by the National Institute of Standards and Technology (NIST)
purported to have validated the capacity of the D-L test to
specifically and definitively identify marijuana. The title of the
article, published in Forensic Science International, "Validation of
Twelve Chemical Spot Tests for the Detection of Drugs of Abuse,"
misstated the researchers' actual findings. In fact, the study's
authors found that the twelve tests it analyzed, including the D-L,
were nonspecific. "The tests," they wrote, "are not always specific
for a single drug or class." Speaking of the D-L test, they wrote that
"mace, nutmeg and tea reacted with the modified Duquenois-Levine,"
meaning that they produced false positives. They also noted, echoing
Maunder's 1969 article, that the D-L test is subjective: "The actual
color...may vary depending on many factors [including] the color
discrimination of the analyst."

The best-known D-L "validation" study, and thus the most damaging to
defendants, was published in 1972 by John Thornton and George Nakamura
in Journal of Forensic Science Society. It instantly made the D-L test
the gold standard across the country for marijuana identification. But
just like the NIST study, this report is internally contradictory and
scientifically flawed.

On the opening page of this article, the authors state that the D-L
test is a "confirmation" test for marijuana.

Such a test must be capable of proving the presence of the drug beyond
a reasonable doubt, specifically identifying the drug to the exclusion
of all other possible substances and producing neither false positives
nor false negatives.

However, the researchers' own findings contradict their conclusion and
show instead that the D-L test merely screens for marijuana.

The authors themselves reported that the D-L test gave false positives
and was not a confirmatory test even when cystolithic hairs -- visible
on the leaves of marijuana and other plants -- are found on the
suspected substance.

They claimed that "the Duquenois-Levine test is found to be useful in
the confirmation of marijuana" when cystolithic hairs are observed
"since none of the 82 species possessing hairs similar to those found
on marijuana yield a positive test." The problem is, as the authors
noted, there are hundreds of plants with cystolithic hairs that they
did not test, making their sample of eighty-two species woefully
inadequate. In effect, they admitted that the botanical exam itself
was nonspecific. Combining two nonspecific tests does not make a
specific, confirmatory test, as the D-L and the botanical exam both
could easily render false positives.

Without having proved specificity, the authors nevertheless claimed
it: "The specificity of the Duquenois reaction has been established,
empirically at least, over the past three decades.

No plant material other than marijuana has been found to give an
identical reaction." They also noted its widespread use as if it were
proof of its efficacy, mentioning that the D-L test was adopted as a
preferential test by the League of Nations Sub-Committee of Cannabis
and that a version of the test was proposed by the United Nations
Committee on Narcotics as a specific test for marijuana. (The UN
subsequently found that only gas chromatography/mass spectrometry
analysis could affirmatively identify marijuana.)

Inexplicably, this Thornton-Nakamura study is cited by the Drug
Enforcement Administration and labs around the country as justifying
the use of the D-L test alone or in combination with the microscopic
visual exam for proving the presence of marijuana in a seized substance.

Even some courts have erroneously ruled that the D-L test is specific
and confirmatory. The most egregious example occurred in 2006. U.S.
District Judge William Alsup found the D-L test to be a specific
identification test and declared, grandiosely: "Despite the many
hundreds of thousands of drug convictions in the criminal justice
system in America, there has not been a single documented
false-positive identification of marijuana or cocaine when the methods
used by the SFPD [San Francisco Police Department] Crime Lab are
applied by trained, competent analysts." In fact, according to an
affidavit in that case from a senior criminologist at the SFPD, its
lab had, for forty years, used the D-L test in combination with a
botanical exam to identify marijuana -- two nonspecific tests that can
each produce false positives. (A spokeswoman says that current SFPD
policy is to subsequently confirm these results with gas
chromatography/mass spectrometry.)

In March 2009, a committee of the National Academy of Sciences,
speaking of the D-L and other tests, called the analysis of controlled
substances "a mature forensic science discipline"; "one of the areas
with a strong scientific underpinning"; and an area in which "there
exists an adequate understanding of the uncertainties and potential
errors." These incorrect assertions relied on assurances from
government witnesses that "experienced forensic chemists and good
forensic laboratories understand which tests (or combinations of
tests) provide adequate reliability." The committee's main witness was
Joseph Bono, the former director of a regional DEA lab, who had
previously issued a sworn affidavit, referring to the D-L and other
forensic tests, which asserted that "tests and instruments that are
properly used by qualified forensic chemists are incapable of
producing a false positive." But experience and competence cannot make
a test specific if it is not -- nor can they make it immune from false
positives.

In 2008, Senator Jim Webb, D-VA, said, in announcing a proposed bill,
that "the criminal justice system as we understand it today is broken,
unfair." This unfairness is visible every day in the disparate and
contradictory court decisions regarding the admissibility of D-L test
results. Not only have courts contradicted one another on
admissibility, but some courts have even chosen to admit the results
of a D-L test while ruling that it does not prove the presence of
marijuana beyond a reasonable doubt.

This patchwork of admissibility means that a person in one state can
be convicted of possessing marijuana on the sole basis of the D-L test
while a resident of another state cannot.

In 1978, the Supreme Court of Illinois in The People of the State of
Illinois v. Peppe Park illustrated this confused, unconstitutional
state of affairs.

In denying the admission of ipse dixit ("It's marijuana because I say
it's marijuana") reports, the court found that "police officers may
not be presumed to possess the requisite expertise to identify a
narcotic substance...because it simply is far too likely that a
nonexpert would err in his conclusion on this matter, and taint the
entire fact-finding process." This court cited a study that found 241
incorrect identifications of marijuana by arresting police officers.

Yet in the same decision, the court erroneously claimed that "to
determine accurately that a particular substance contains cannabis,
all that is necessary is microscopic examination combined with the
Duquenois-Levine test."

Challenging the Test

Robin Rae Brown never even faced trial on marijuana possession
charges. After she was released from jail, she retained this author as
a defense expert. When I first spoke with her attorney, Bill Ullman,
he had never heard of the D-L test and said he normally plea-bargained
cases like Robin's. I urged him to challenge the test and provided him
with several scientific studies cited in this article, relevant court
decisions, including Jackson v. Virginia, and other information. When
Ullman made inquiries, he discovered that the sheriff's department had
never performed a lab test to confirm his field test results.

Robin, he discovered, had been charged with a felony solely on the
basis of the D-L test and Officer Raimondi's "opinion."

At Ullman's insistence, the sheriff's department finally performed a
gas chromatography/mass spectrometry (GC/MS) analysis on Robin's
smudge, which came out negative.

State Attorney Berki Alvarez immediately dropped the charges against
her, noting to Ullman, "the scariness that a person could be arrested
under such conditions."

Even scarier was the lab's revelation that it does not conduct GC/MS
analysis until just before a trial, as most marijuana possession
defendants plea bargain before the trial.

If Robin had accepted a plea bargain, she would have been wrongfully
convicted and saddled with a criminal record that could have damaged
her future job prospects.

How many others before and since have accepted plea bargains based on
false positives from a D-L test?

"I am just now willing to share this story," Robin wrote months after
her arrest, "because it was embarrassing and I didn't want to worry my
family and friends." After some serious thought, she recently decided
to file a lawsuit for wrongful arrest. "I would like to see them stop
using the bogus field tests and to improve their procedures at the
county crime lab," she says. "I would like the public to be aware of
the faulty field tests."

In truth, everyone arrested on marijuana charges has a Constitutional
right to a GC/MS analysis.

Otherwise, they are being denied both due process and a fair trial.
"It is not only unnecessary for the courts to continue to accept
conclusory drug identifications based on nonspecific tests, it is also
unwise for them to do so," wrote Edward Imwinkelried, a professor of
law at the University of California at Davis whose work on scientific
evidence has been cited by the Supreme Court. "Conclusory drug
identification testimony is antithetical and offensive to the
scientific tradition, and courts should not allow ipse dixit to
masquerade as scientific testimony... Even more importantly, sustaining
such drug identifications places a judicial imprimatur on testimony
that cannot justifiably be labeled scientific. The rejection of such
identifications is necessitated not only by due process but also by
the simple demands of intellectual honesty."

Sustaining evidence from nonspecific tests like the D-L, he concludes,
"is both bad science and bad law."