The High Road

An initiative to legalize marijuana has drawn the ire of some pro-pot advocates, who oppose a provision that treats stoned drivers like drunks.

Early on the drizzly evening of March 4, 2011, a state trooper patrolling suburban Skagit County spotted a beige Volkswagen Jetta cruising down State Route 20 with a broken taillight. He flashed his lights, sounded his siren, and pulled over the infringing vehicle in the municipality of Sedro-Woolley. According to his report from the stop, the moment the trooper leaned into the window to ask for the driver’s license and registration, he detected “the strong odor of marijuana.”

Nearly a year later, the driver, 53-year-old Allison Bigelow, recalls how intensely she must have reeked of reefer at that particular moment. A heavyset woman with oval glasses and waist-length blond hair, Bigelow is authorized to use medical marijuana to treat a debilitating back injury suffered in a car accident several years ago. She grows her own supply, and had been gardening that afternoon. “I had some equipment in my car which I probably shouldn’t have had,” Bigelow explains. “Plus I had been trimming plants, and I smelled like fresh cannabis. My hands were still sticky.”

Bigelow told the trooper it had been approximately eight hours since she’d last smoked pot. He was unconvinced, and asked her to perform the standard battery of field sobriety tests. The officer noted that Bigelow seemed unable to understand his instruction to walk heel-to-toe in a straight line, and that she swayed and lost her balance during the exercise. Then she teetered again, waving her arms as she tried and failed to stand on one leg. When she was supposed to count off 30 seconds in her head, she stopped after 23.

Bigelow was arrested on suspicion of driving under the influence of marijuana. She was—and still is—indignant about the charge. She insists it had been multiple hours since her most recent toke, and that, given her back condition, she was worried she’d wind up in the ditch during the heel-to-toe and balance exercises.

“I hadn’t done anything like that for years,” Bigelow says. “He basically said I had a hard time understanding the instructions, but I was mostly debating with him about whether I could do it without falling on my face.”

In addition to the grow-op supplies, a subsequent search of her car turned up a single joint, which hadn’t yet been sparked. A blood draw, taken roughly half an hour after she was placed in the back of a squad car, showed 18.3 nanograms of THC (tetrahydrocannabinol, the psychoactive chemical compound in marijuana) per milliliter of blood in her system—a level that is relatively high compared to a baseline of zero, but not necessarily an indicator that she had been hot-boxing her ride like Snoop Dogg.

There is currently no legal limit for THC blood levels in Washington as there is for blood alcohol content, but that could change before the end of the year. Initiative 502, slated to appear on the November ballot, proposes legalizing, taxing, and selling (in state-run stores) marijuana for recreational use. It would permit possession of up to an ounce of pot, but also set a strict limit of 5 nanograms of THC per milliliter of blood for Washington drivers over age 21, and impose a zero-tolerance standard for younger motorists.

Some medical-marijuana patients and activists, doctors, lawyers, and even a state lawmaker known for taking a tough stance on alcohol DUIs are concerned that the otherwise progressive ballot initiative to decriminalize marijuana possession could inadvertently put thousands of stoners at risk of being busted for DUI, even if they are driving completely sober. The conundrum has left some longtime crusaders for marijuana-law reform in the awkward position of opposing the measure.

“It would be historic legislation,” says Vivian McPeak, co-founder of Hempfest, Seattle’s annual gathering to advocate marijuana decriminalization. “I’ve tried and tried to find a way to back this because my life is so dedicated to this cause. I just don’t think it’s fair to ask cannabis users, medical users especially, to trade their driver’s licenses for an ounce of pot.”

Proponents of I-502—an esteemed group that includes the local ACLU chapter’s drug-policy director Alison Holcomb, former U.S. attorney John McKay, and travel guru Rick Steves—argue that the DUI fears are overblown, and the greater goal of legalization trumps all. “It would be a shame to basically oppose I-502 on a possibility, versus embracing something that can end real harm right now,” says Holcomb, the campaign director for New Approach Washington, the political action committee behind the initiative. “It’s just not reality that officers will start pulling over people randomly, illegally arresting them, and taking them in to get blood draws.”

But Bigelow suspects that she and other heavy users might never make it below 5 nanograms. She and a few other patients recently had their blood tested by a doctor after a night’s sleep. Troublingly, her sample contained more than twice the proposed limit of THC—even though it had reportedly been nearly 12 hours since she’d previously smoked.

Bigelow’s experience jibes with some of the leading scientific research on the subject of driving while high, which says not only that stoners exhibit behavioral and chemical signs of impairment dramatically different than drunks do, but that habitual smokers could test positive for THC after extended periods of abstinence. Answering the question of whether the proposed THC blood limit would spur a significant increase in DUI arrests and prosecutions, however, is hardly so straightforward.


Initiative 502 could effectively end pot prohibition in Washington. It would create a network of state-licensed growers, processors, and stores, and levy a 25 percent excise tax at each stage of the supply chain. Adults 21 and older could purchase and possess up to an ounce of dried marijuana, one pound of marijuana-infused product in solid form (i.e., brownies), or 72 ounces of marijuana-infused liquids. The millions of dollars in revenue reaped from the drug sales would be earmarked for substance-abuse prevention, education, health care, and the state’s general fund.

At a hearing last month in Olympia, a bipartisan group of lawmakers seemed both intrigued and amused by the proposal. Rep. Sam Hunt (D–Olympia), who chairs the House State Government & Tribal Affairs Committee that was reviewing the initiative, joked about how he was presiding over a “joint panel . . . no pun intended” before soliciting testimony from both supporters and opponents of the initiative.

McKay, a Republican and an outspoken supporter of drug-law reform since stepping down as federal prosecutor in 2007 (see “The Evolution of John McKay,” SW, Sept. 28, 2011), emphasized that the black market for marijuana creates “an enormous flow of money to dangerous drug cartels, to gangs, and thugs” which could be undercut by I-502. University of Washington professor Roger Rothman, an addiction expert, said that current pot laws “misuse the criminal-justice system to deal with a public-health problem.”

On the opposite side of the issue, Steve Freng of the Office of National Drug Control Policy argued that “it’s silly to think the cartels will simply pack up and leave the state with their tails between their legs” if the state legalizes their primary cash crop. He also said that the measure would make pot more available to children, a claim met with skepticism by several committee members.

The only question raised about the divisive DUI provision came after the hearing, in a press conference featuring I-502’s marquee backers. Dr. Kim Thorburn, Spokane County’s former top public-health official, was dismissive. “In order to be stopped for impaired driving, you have to show impairment,” she said. “This is not a concern for medical-marijuana users, and has been kind of a red herring that has been raised.”

Ultimately the lawmakers took no action on the initiative, thus assuring it a spot on the ballot. Holcomb cites polling which shows that DUI provisions make marijuana legalization more appealing to ambivalent voters, and says these provisions could be a deciding factor, given the increased voter turnout expected in this presidential election year.

In particular, Holcomb points to Prop 19, the failed marijuana-legalization initiative in California in 2010. Polling after the fact showed that undecided voters had been swayed by arguments from Mothers Against Drunk Driving and the California Highway Patrol that hammered the proposal’s lack of a DUI standard. Holcomb says the authors of I-502 performed similar research in Washington, asking whether prospective voters would be more inclined to support marijuana legalization if the law included a blood limit “roughly analogous” to the .08 standard for alcohol.

“The results were overwhelming,” Holcomb says. “People said they would be more inclined to support a legalization measure with such provisions. Sixty-two percent of respondents said they’d be more likely to support it, and only 11 percent said they’d be less likely.”


What irks critics of I-502 is that “roughly analogous” is an awfully subjective phrase, especially when it comes to the science of judging a stoned driver’s level of impairment. Decades of exhaustive scientific research have concluded that alcohol tends to produce uniform effects, and that .08 is the level at which drunk drivers begin to pose a risk to themselves and others. With marijuana, the effects are far less consistent, and the impact on driving ability is still largely inconclusive—particularly with regard to medicinal smokers.

“We do not know what the levels mean in these people,” says Dr. Jennifer Souders, a clinical associate professor of anesthesiology and pain medicine at the University of Washington and an expert witness in cannabis DUI cases. “To include them in this law when there’s no data on them is scientifically irresponsible and without merit.”

As it stands, Washington is one of the last states to operate in a legal gray area for driving while high. Among the 15 states that sanction medical marijuana, Nevada and Ohio have 2-nanogram limits for THC. Twelve states have a zero-tolerance policy for driving under the influence of any illicit drug, including marijuana. Arizona has the most draconian law on the books, with mandatory jail time for anyone who tests positive for even carboxy-THC, an inactive metabolite that can linger in the body for weeks after an individual’s most recent bong hit.

DUI prosecutions typically focus on the level of active THC in the blood, a figure that varies widely based on the potency of the pot, the frequency of use, and the manner in which it was taken into the body. In smoking, the THC level generally spikes at 50-plus nanograms immediately after inhalation, then dissipates rapidly, usually disappearing within one to four hours for occasional users. But when edibles are used, or when a smoker already has a lingering amount of THC in his or her system, several scientific studies—including the one that was the basis for I-502’s proposed limit—have concluded that significant levels of THC will be detectable long after the high has worn off.

The 5-nanogram standard in I-502 is largely based on a 2005 study from a group of 11 international scientists, led by Germany’s Dr. Franjo Grotenhermen. The researchers caution that “empirical evidence on cannabis and driving is still much less conclusive than that for alcohol,” but suggest that a 5-nanogram limit “may achieve a reasonable separation of unimpaired from impaired drivers, who pose a higher risk of causing accidents.”

It’s important to note, though, that Grotenhermen and his colleagues devised their standard for infrequent users. The researchers caution that routine tokers “may present measurable THC concentrations at all times.” They also point out that exposure to secondhand smoke could result in false positives, meaning that a zero-tolerance standard like the one proposed for minors in I-502 “facilitates law enforcement but is not based on science and does not target impaired drivers.”

Still other research suggests that the risk of driving after a few puffs of grass is minimal. Studies have shown almost universally that people should wait at least an hour to get behind the wheel after they inhale and avoid combining alcohol with THC. But a 2009 report from the Yale University School of Medicine concluded that, by and large, stoned drivers display “an increased awareness that they are impaired” and “tend to compensate effectively.”

In 1993, the U.S. Department of Transportation commissioned a study entitled “Marijuana and Actual Driving Performance.” In addition to observing joint-smoking drivers in action, the agency reviewed the role of drug use in fatal crashes. “In high-density urban traffic . . . THC did not impair driving performance,” the findings state. “There is little if any evidence to indicate that drivers who have used marijuana alone are any more likely to cause serious accidents than drug-free drivers.”

When Colorado proposed a 5-nanogram standard last year, the state legislature was besieged by complaints from the state’s well-organized medical-marijuana lobby. The lawmakers convened a “marijuana DUI workgroup,” asking stakeholders on both sides of the issue to analyze the proposal. The group recommended against adopting THC blood limits.

Michael Elliott, executive director of Colorado’s Medical Marijuana Industry Group, was a member of the panel, and he says the conflicting literature was a key factor in their decision. “This is like global warming,” Elliott says. “I’ve got my research that says my thing and the opposition has their research that says the exact opposite. Both sides say it’s about research, but really it’s all about politics.” In spite of the recommendation of Elliott’s workgroup, the state legislature is still considering implementing a 5-nanogram per se standard. Colorado is also considering a ballot initiative similar to I-502, but that one does not include a THC blood limit.


In an unassuming three-story building on Airport Way, about a mile southeast of Safeco Field, stands a massive stainless-steel refrigerator. A bright-orange biohazard sticker warns that the fridge contains something other than snacks: namely, thousands of blood-filled vials collected as evidence in criminal investigations across Washington and Alaska, all awaiting analysis by the lab technicians using high-powered computers and scientific instruments in the adjoining rooms.

The building and blood belong to the State Patrol’s toxicology lab, which processed 1,060 blood samples last year in DUI cases that tested positive for marijuana. Roughly half of those involved pot combined with alcohol or other drugs. According to Fiona Couper, the lab commander, cannabis DUIs account for about one-fifth of their total workload, though she cautions the number could be higher because samples that test positive for blood-alcohol concentrations greater than .10 aren’t always screened for THC and other substances.

The THC in samples analyzed by the lab last year ranged from 1 to 58 nanograms per milliliter of blood, with an average of 6.6 nanograms. Couper says samples that test below 1 nanogram aren’t reported because the accuracy below this concentration cannot always be established. But even in cases where the THC levels are clearly elevated, Couper and her colleagues can’t testify in court that the drug directly correlates to impaired driving. “We’re far less comfortable with equating specific signs of impairment to a THC concentration than we are with alcohol,” Couper says. “We typically don’t go into court and say—I’m throwing out a figure here—10.3 nanograms of THC caused these symptoms. We’ll come along and say ‘This is the result of the testing, these are the general effects of THC, and then this can be matched up to the impairment observed by the officer.’ Then it’s the judge or jurors’ role to decide whether the impairment was likely due to marijuana use.”

The State Patrol has 238 “Drug Recognition Experts” trained to spot the symptoms of drug and alcohol abuse. Sgt. Mark Crandall, DRE program coordinator, says stoned drivers typically have a hard time understanding instructions, and have watery, bloodshot eyes with dilated pupils. He declined to comment on how I-502’s 5-nanogram “per se” (a legal term that means a certain act is inherently illegal) standard would impact the work of state troopers, but emphasizes that probable cause is required to make a traffic stop and arrest. “Per se is really irrelevant,” Crandall says. “I really don’t care about the levels in the blood. It’s the signs and symptoms of impairment that are important.”

Aaron Pelley, a Seattle attorney who specializes in medical-marijuana cases, says the notion of probable cause sounds good in theory, but the reality is cops can use practically any excuse to pull over a suspect. “It’s only a matter of time until the officers will find a reason to stop you,” Pelley says. “There are hundreds and hundreds of ways for the officer to pull you over for a traffic violation.”

Pelley says that about 30 percent of his clients are medical-marijuana users, and he has noticed an increase recently in routine traffic stops involving patients that turn into DUI prosecutions. The observations of state troopers and the results of field sobriety tests can be damning in such cases, but under the current law, there is some wiggle room for people accused of driving while high. THC blood levels are admissible as evidence, but other factors, such as the circumstances that led to the traffic stop, can be taken into account as well. That leeway all but vanishes with per se limits.

“There’s no defense,” says Paul Armentano, deputy director of the National Organization for the Reform of Marijuana Laws, or NORML. “You broke the law by operating a motor vehicle with that level of THC in your blood. It’s divorced from impairment. It becomes very, very convenient for the state to gain a conviction, much more so than it is now when the state has to have their ducks in a row and present evidence of actual impairment and recent drug use.”

But, according to Armentano, who has also testified as an expert witness in more than 50 marijuana DUI cases around the country, there has never been a comprehensive study to assess whether the rate of marijuana DUIs increases or declines after states enact THC blood limits. “None of these states keep good records of that information,” he says. “There’s not any data whatsoever that seems to have been gleaned from any real-world experience from these laws.”

Anecdotal evidence suggests such laws do not result in law enforcement having a field day with stoned drivers. Pennsylvania implemented a 5-nanogram “guideline” for pot DUIs in 2003, but tightened its regulations last April by enacting a strict 1-nanogram THC blood limit. Michael Worgul, a Pittsburgh criminal-defense attorney specializing in DUI and marijuana cases, says the impact on his clientele has been negligible. “We hardly see any marijuana DUIs,” Worgul says. “Of the DUI cases I’ve handled here in Pennsylvania, 99.9 percent are alcohol-related. Marijuana might fall into that one-tenth of a percent.”

In King County, Amy Freedheim, the deputy prosecutor in charge of felony traffic cases, says she treats medical marijuana like any other prescription drug. She says she is wary of THC blood laws because medical patients can easily develop a tolerance, much as users of OxyContin and other painkillers do. Although 5 nanograms or more of THC would typically trigger a DUI prosecution, especially if the driver is involved in an accident, Freedheim cautions that it’s important to use discretion and take all the facts into account. “If you’re impaired, you should be prosecuted,” Freedheim says. “I have not had any problem currently with evaluating cases where I have marijuana, or somebody has marijuana on board. It is a drug, and I evaluate it accordingly.”

Last year, before I-502 came into being, the state House of Representatives considered legislation that would have enacted an 8-nanogram THC blood limit for motorists. Freedheim cautioned state Rep. Roger Goodman (D-Kirkland), the bill’s sponsor, that the science on per se THC standards is still unsettled. That was enough to make Goodman rethink the proposal.

Goodman has made DUIs a cornerstone issue in his political career. This year he has proposed tightening regulations on interlock-ignition devices, along with several other crackdowns related to alcohol DUIs. Goodman is also in favor of marijuana decriminalization, but he says he can’t endorse I-502 because of the DUI provision.

“I realized the science is very scant and unreliable, and that we should not be basing policy on assumptions,” Goodman says. “We should be holding people accountable for driving impaired, but not holding people accountable for merely driving with certain metabolites in their body that don’t have an effect on their driving. We need to be fair, not punish people needlessly for using a substance in the past that doesn’t affect performance in the present.”


When she was arrested last March, Bigelow’s attorney told her she had a 50/50 chance of winning the case in court. Unwilling to risk the severe repercussions of a DUI conviction, she pleaded guilty to a reduced charge of negligent driving, paid more than $4,000 in fines and court costs, and is still on probation.

She still takes strong doses of cannabis several times daily, and was anxious about reoffending even before the ballot initiative came along. Now she’s afraid a 5-nanogram standard might make it impossible for her to drive legally. “I’d probably never make it down to five,” she says, “even if I don’t use cannabis throughout the entire day.”

Bigelow’s pot doc is Gil Mobley, an outspoken critic of I-502. In addition to writing medical-marijuana authorizations from his office in Federal Way, Mobley practices occupational medicine, performing drug screenings for the Department of Transportation and private companies. He has no qualms about delivering urinalysis results that could cost employees their jobs, but believes a 5-nanogram THC blood limit for drivers would do more harm than good. “The fact that they’re trying to base this on a BAC [blood-alcohol content] model is senseless,” Mobley says. “It bothers me. The science isn’t there. Tens of thousands of people will be doing something illegal the minute that passes.”

Mobley serves as the spokesperson for the recently formed political action committee No on I-502. When Bigelow asked about testing her baseline THC levels to get a sense of how long she ought to wait before driving, the activist doctor went a step further and offered to perform blood tests before and after smoking, combined with a neurological exam and the state patrol’s standard field sobriety test.

Another of Mobley’s patients expressed interest in trying a similar battery of tests, and opted to take part. He requested anonymity for this story, citing medical privacy concerns, and picked the amusingly appropriate pseudonym Pavlov. Bigelow’s teenage daughter, Chanterelle, and Troy Barber, a member of the anti-I-502 group Sensible Washington, also asked to be checked out to see whether secondhand smoke might trigger detectable THC blood levels.

Lounging on uncomfortable couches, filling out paperwork, and reading magazines as they would at any other trip to a doctor’s office, the group of four listens as Bigelow recounts the story of her DUI arrest. “The officer didn’t ask to see my patient documentation until the very end,” Bigelow says. “He said something like ‘Maybe next time you should get your errands done in the morning before you take your medicine.’ I told him I’m a safe driver. I don’t use drugs or alcohol, and I don’t use other medicines.”

“She is a really good driver, like, all the time,” Chanterelle chimes in. “Sometimes she’ll forget her blinker, though, and I’m like, ‘Mom!’ “

Mobley’s nurse summons the patients to draw their blood, and without fail they each wince when she pokes a needle through their skin and draws the crimson fluid into a test tube. One by one, Mobley invites them into a separate room and asks a series of questions about their marijuana use. Bigelow tells him she typically smokes two joints in a single sitting, four or five times a day. She says she had most recently smoked 11 hours prior to the exam, around midnight the previous evening.

With his white lab coat, close-cropped gray hair, and methodical efficiency, Mobley looks every bit the experienced doctor as he gives instructions with a faint Southern drawl. He asks Bigelow to walk heel-to-toe and stand on one leg. He tracks her eye movements with a small flashlight. He tells her to count down from 98 in increments of seven, rather than reciting the ABCs backward as in the classic field sobriety quiz. “I can’t do it myself,” Mobley jokes. “So I don’t put my patients through it.”

Other than wobbling a bit while standing on one leg, Bigelow passes with flying colors. Adding another task to the sobriety tests, Mobley gives her three nouns—”tree, can, and mouse”—to repeat later, and asks her to recite a tongue-twister. He also has her glance at a drawing of pentagons with intersecting lines, then reproduce the image with a pen and paper. Finally, he tests her reaction time by dropping a measuring stick and noting how many inches it falls before she catches it. Once again, Bigelow’s performance is error-free, and she registers what seem like respectable reaction times with the measuring stick.

Pavlov, a middle-aged man with a short ponytail and a stubbly gray beard, tells Mobley that he smokes “pretty much every day” to soothe arthritis-like symptoms, but hasn’t lit up for 15 hours or so. He breezes through the tests, as do the nonsmokers, Barber and Chanterelle.

The group leaves for about 45 minutes, and returns smelling noticeably of pot. Bigelow says she smoked her standard two joints, with Pavlov taking a few hits off of one. The bystanders say they were in an enclosed car with the smokers the entire time. The nurse draws their blood a second time, and Mobley repeats the tests as before, varying the memory questions.

This time, Bigelow slips up trying to repeat “How much wood could a woodchuck chuck,” and grimaces in pain while standing on one leg, but doesn’t lose her balance. Her reaction time on the ruler drop increases by a few inches. “I actually thought she showed some improvement overall,” Mobley says. “But that could just be familiarity with the test. She’s a large woman and it’s hard for her to balance because of the pain, but otherwise she did flawlessly.”

The two who abstained from smoking show no noticeable changes from the initial go-round. Pavlov, meanwhile, has a more difficult time walking heel-to-toe, and loses his balance after a few seconds of standing on one leg. “I have very stiff legs at the moment,” he says self-consciously. He aces the nouns and backward spelling, and, like Bigelow’s, his reaction time also improves slightly in the ruler grab. This time, though, he closes his eyes and rubs his temples while counting backward from 100 by sixes.

Afterward, Pavlov seems embarrassed about losing his balance, but says he’d have no problem getting behind the wheel. “I feel like it hits me pretty hard in about the first 45 minutes after I smoke,” he says. “But normally I drive after that. I’m anxious to see the results of the blood test. My reaction time was faster [in the ruler test] when I’m high. I thought that was pretty cool.”


In late February, NORML, perhaps the country’s most respected marijuana-advocacy organization, officially endorsed I-502. Considering the mounting opposition to the measure, particularly in Washington’s medical-marijuana community, it was a contentious move. In making the announcement, NORML’s outreach coordinator, Russ Belville, slammed the DUI provision, describing the 5-nanogram limit as “unnecessary, unscientific, and unjust,” but also chastised groups like Patients Against I-502, calling them “Patients Against Pragmatism.”

Belville estimates that 630,000 people in Washington use marijuana at least once a year, and fewer than 100,000 have medical authorizations. He acknowledges flaws in the proposal, but emphasizes that it represents a realistic chance to legalize marijuana, a point that cannot be overlooked. “Nobody is throwing the patients under the bus,” he says, addressing a common opposition claim. “I-502 is just asking that the healthy tokers not have to sit in the back of the bus anymore, and that the sick tokers ride one if they don’t drive well.”

Infighting among Washington’s marijuana activists is hardly unprecedented—a proposal to overhaul the state’s policies on marijuana dispensaries prompted similar squabbling earlier this year—but career reformers say things have never gotten quite as heated as they have with I-502. “For years we had this kumbaya, warm-and-fuzzy thing going on,” Hempfest’s McPeak says. “We disagreed on the nuts and bolts [of legalization], but it was so far away it didn’t matter. It’s good we’ve reached this stage, but it’s bad that it’s creating so much animosity among folks who have been working together for years.”

Beyond the THC blood limit, I-502’s most zealous detractors complain that the initiative does not permit smokers to grow their own supply, and claim that it creates a state monopoly on the bud business. They also echo concerns once voiced by Gov. Christine Gregoire that state employees could be at risk of federal prosecution for distributing marijuana.

But the DUI provision is clearly the wedge issue with the most traction, and Holcomb worries that self-interest could get in the way of the greater good. “I have some concern that a few of the people that are yelling the loudest about the DUI provision are just opposed to I-502 for some other reason,” Holcomb says, “and this is the hook that they’re using and drumming up a lot of fear, in the medical-marijuana patient community especially, that is unfounded.”

When California’s legalization initiative was narrowly defeated in 2010, interest groups that capitalize on the medical-marijuana industry—doctors, lawyers, dispensary owners, and the like—were generally pleased to see their source revenue remain untouched. A similar dynamic could be fueling the anti-legalization sentiment in Washington’s pro-pot circles, although even those who stand to profit from a surge in DUI arrests—such as Pelley, the cannabis DUI attorney—claim that’s not the case.

“There’s nothing more I want to do than support this,” Pelley says. “It is such a huge step forward in reform of law in terms of criminal-justice-system resources wasted on marijuana cases. It’s hard to see past that, but you have to figure out, how many lambs am I taking to the slaughter in the name of accomplishing this goal?”

The King County Bar Association has endorsed I-502, along with the Peace and Justice Action League of Spokane. Other interest groups—such as Physicians for Social Responsibility and the Washington Association of Criminal Defense Lawyers—have yet to endorse or reject the measure.

The simplest solution—striking the DUI provision from I-502, or rewording it to exempt medical users—is not feasible. At this stage of the initiative process, making changes would require organizers to gather another 241,000 signatures to reclaim their proposal’s place on the ballot. If approved by voters, the state legislature would have to wait two years before tweaking the law, and muster a two-thirds majority vote to do it. The most likely scenario, according to Holcomb, is that lawmakers could amend the state’s medical-marijuana law with language that lets authorized users off the hook by requiring proof beyond a blood test for a DUI conviction. Two such bills were proposed earlier this year. Both quickly fizzled.

With no easy fix, I-502 critics like Mobley worry that marijuana DUIs could become as common as misdemeanor possession arrests. A week after his informal study with Bigelow and the others, he reported that Bigelow’s blood had 11.7 nanograms of THC in her blood before smoking and 41.9 nanograms afterward. Pavlov had zero nanograms in the first blood draw, 11.5 post-toke. For the abstainers, the results were negative on both tests.

Though hardly definitive proof that a 5-nanogram blood limit would jeopardize the livelihoods of thousands of medical-marijuana patients, Mobley insists that these results indicate that folks like Bigelow will have a tough time ever getting their blood levels down to a level that isn’t incriminating. “In chronic, seasoned users there is virtually no compromise in their skills,” Mobley says. “Neurologically, they are fine. They can pass a sobriety test with no problem. There are grave implications with this [initiative], not only for patients but individuals who hope to use cannabis recreationally as well—they just won’t be able to drive legally.”

Whether such fears amount to paranoia remains to be seen, as does the question of whether the 5-nanogram limit in I-502 will woo more voters than it scares away. At least according to Holcomb, the DUI compromise could be the key to Washington’s taking a giant leap forward in marijuana policy.

“The bottom line,” Holcomb says, “is if we want to pass legalization in 2012, we need to meet the voters where they are. Where they are right now is more scared of people driving high than worried that medical-marijuana patients will get arrested for DUI.”

Dr. Gil Mobley tests Allison Bigelow’s sobriety.

Dr. Gil Mobley tests Allison Bigelow’s sobriety.