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Cannabis trends across Washington state

Criminal justice data

Law enforcement's de-emphasis of enforcement and prosecution of marijuana crimes (use and low level dealing) and legal medicinal marijuana sales were part of the context in which support for I-502 grew. Below, we present counts of cannabis and hashish criminal violations collected by the Washington Association of Sheriffs & Police Chiefs and law enforcement drug evidence testing cases reported by the state crime lab (the Washington State Patrol Forensic Laboratory Services Bureau) with positive findings for any amount of cannabis, cannabis derivatives, and related compounds.

A "cannabis case" refers to a unique lab case number with at least one result positive for any form of cannabis, including hashish. Crime lab cases reflect a combination of who gets arrested, which cases get prosecuted, which items get sent to a lab for testing, and whether the items have sufficient quantity to be tested. Rates and trends may thus be influenced by policy and practice factors such as de-emphasis, increased enforcement of medicinal marijuana regulations, and legalization of recreational cannabis. Note that the latter did not eliminate the black market for marijuana.

Cannabis cases over time

Marijuana violations dropped substantially, more than 50%, from 2012 to 2013; I-502 passed November 2012. Note that the National Incident-Based Reporting System replaced the Uniform Crime Reports Summary Reporting System in 2012 precluding presentation of long term trends. (Specifically, we add drug/narcotic violations reported to involve "Marijuana" and "Hashish". While the source is not clear that these are not mutually exclusive and that a case could involve both--and thus be double counted--the number of hashish cases is very small compared to marijuana cases--e.g., 26 versus 2580.) The crime lab data, police evidence that is generally tested in preparation for prosecution, indicate that this decrease was occurring long before 2013. We show three different policy environments in place in the background of the figure.

For crime lab cases, we also present trends for pharmaceutical cannabinoids available by prescription (currently dronabinol and nabilone) and cannabimimetics (Spice, K2, etc.). Cannabimimetics are synthesized drugs that create some marijuana-like effects. They are increasingly being regulated as Schedule 1 drugs by the DEA (no legal use) while some are still available on the internet and in convenience stores. An important added complication for crime lab testing of both these comparison groups is the need for a standard to which to compare the lab sample for identification. Cannabimimetics in particular is a constantly changing class of drugs in which as soon as a particular formulation (e.g., JWH-018) gains enough notoriety--usually, being made illegal--to warrant a standards company producing a chemical standard and a crime lab buying it, the formulation is changed (e.g., to JWH-073). Thus, identified crime lab cases do not capture the rise of a particular cannabimimetic, but at best its peak and decline. To better see the trends in the comparison categories, click on the series names "Violations" and "Cannabis and derivatives" in the legend to turn off the higher series.

Data sources: Forensic Laboratory Services Bureau, Washington State Patrol (crime lab drug cases), Washington Association of Sheriffs & Police Chiefs (cannabis violations)

As a share of all drug cases

While the above charts looked at counts of drug cases, below we focus on what proportion of all drug cases involved the same drugs of interest. This helps us understand how prominent the drug class has been in law enforcement case loads, which of course reflects not only prominence among drug users but also prominence among law enforcement and among distributors and dealers and the testing issue highlighted above. Again, to highlight the less common categories and better see their growth, turn off the "Cannabis and derivatives" series by clicking on the name in the legend.

Data sources: Forensic Laboratory Services Bureau, Washington State Patrol

Cannabis cases: Not all counties have seen declines

Below, we compare crime lab cases by county, aggregated over an earlier period, after the approval of medical marijuana in 1998, versus a later period immediately following the passage of I-502 and the first 3 years of implementation. Only crime lab submissions from an agency clearly operating within a single county were associated with a county. Those originating from multi-county agencies, such as cross-jurisdiction drug task forces, some Washington State Patrol detachments, or federal law enforcement, are included in the state-wide rate but not the county rates in the maps below. Although implementation of I-502 took time, many jurisdictions in Washington state responded to its passage by dropping existing misdemeanor marijuana cases and de-emphasizing future arrests. A consistent and substantial decline in cannabis-involved crime lab cases occurred throughout the state--except for three small counties (Garfield, Okanogan, and Adams, collectively 0.9% of the state population) where rates for cannabis cases more than doubled. The largest decline was seen in Walla Walla County, which in 2002-04 had the highest rate of marijuana crime lab cases, nearly 208 per 100,000 residents per year, and saw this rate reduced to 10.5 cases per 100,000 residents per year in 2013-15.

Data sources: Forensic Laboratory Services Bureau, Washington State Patrol (cases), Washington State Office of Financial Management (population)