Medical marijuana dispensaries -- with storerooms of high-priced weed, registers brimming with cash and some clientele more interested in getting high than getting well -- are often seen as magnets for crime, a perception deepened by a few high-profile murders.
But a report from the Rand Corp. reaches a startling conclusion: The opposite appears to be true.
In a study of crime near Los Angeles dispensaries -- which the investigators call the most rigorous independent examination of its kind -- the Santa Monica-based think tank found that crime actually increased near hundreds of pot shops after they were required to close last summer.
"What I would take away from it is maybe there should just be a little bit less fear about having dispensaries," said Mireille Jacobson, a health economist who was the lead researcher. "Hopefully, this injects a little bit of science into the discussion."
The researchers compared the 10 days before the city's medical marijuana ordinance took effect June 7, 2010, with the 10 days after, when many of the more than 400 illegal dispensaries shut down -- if only briefly.
They found a 59% increase in crime within three-tenths of a mile of a closed dispensary compared to an open one and a 24% increase within six-tenths of a mile.
The city attorney's office, which has argued in court proceedings that the number of dispensaries needs to be reduced to deal with "well-documented crime," called the report's conclusions "highly suspect and unreliable," saying that they were based on "faulty assumptions, conjecture, irrelevant data, untested measurements and incomplete results."
In particular, the office challenged the idea that most dispensaries closed June 7, 2010, and were not open for at least 10 days. And it offered its own conjecture for the rise in crime: infighting among collective members, increased traffic for pot fire sales and customers disgruntled to find their dispensary closed.
Jacobson said Rand did not assume dispensaries shut down exactly on that date and said that, if more of them closed earlier or later, it would mean only that crime increased more than the report found. The researchers acknowledge that the results are subject to a large margin of error, so the increase in crime within less than a third of a mile could range from as low as 5.4% to as high as 114%.
"These are noisy data over a short period of time," Jacobson said. But she noted that the numbers, which were subjected to complex statistical analyses, clearly show crime increased.
The researchers did not try to draw conclusions on why crime rose, but offered the hypothesis that dispensaries may heighten security in the areas around them because they employ cameras and guards, increase late-night foot traffic, replace illicit street sales and draw heavier police patrols.
In a review of crime statistics from 2009 ordered by Los Angeles Police Chief Charlie Beck, the LAPD found that banks were much more likely to be robbed than dispensaries.
Cmdr. Andrew Smith, a department spokesman, said the LAPD had not yet reviewed the report, but would do so.
The Rand report notes that police departments in Denver and Colorado Springs, Colo., also studied crime around dispensaries and found no evidence that they attracted crime.
None of this surprises dispensary owners or their lawyers, who note that their surveillance records are sometimes requested by police to investigate crimes unrelated to selling marijuana.
"It's some empirical evidence that demonstrates that the security measures that make it safe for patients to obtain their medical marijuana also serve the community," said David Welch, a lawyer who has represented many L.A. dispensaries.
Yamileth Bolanos, who runs PureLife Alternative Wellness Center on South La Cienega Boulevard and also is president of the Greater Los Angeles Collectives Alliance, said, "I know that there's no crime around here. We watch everything."
But Steve Whitmore, a spokesman for the Los Angeles County Sheriff's Department, strenuously disagreed with the report's conclusions. "Every time we shut down a dispensary, the crime and the disorder decrease," he said.
The report looks at such crimes as assaults and thefts, but not "disorder," nuisances such as loitering, double parking, loud noises and graffiti that sparked anger among neighborhood activists. Whitmore said those complaints are often what causes officials to act.
Eagle Rock, which has about a dozen dispensaries, has long been one of the city's pot hot spots.
Michael Larsen, president of the neighborhood council, said he only knows of one dispensary-related crime -- an armed robbery -- but has heard countless complaints from irritated neighbors. He said most dispensaries that initially closed last summer have reopened, defying the city.
"Our main concern is the crime of illegal dispensaries illegally selling marijuana," Larsen said. "That's the crime that we're concerned about."