(Updated 4/24/15) *Note*: Following the publication of this report last month, the Drug Policy Alliance (DPA) was contacted by the Colorado Judicial Branch (CJB). The CJB notified DPA that the data CJB provided to DPA was incorrect. According to CJB’s Court Programs Analyst, the query used by CJB to compile the data “duplicated and in some cases quadrupled charge counts” for the years 2010 and 2011. Below is a revised press release with a link to the revised report, which reflects the CJB’s corrected data.

While it’s unfortunate that we were provided incorrect data by the Colorado Judicial Branch, the report’s good news remains the same: Across all categories, marijuana arrests have drastically plummeted in Colorado following the passage of Amendment 64.

All eyes are on Colorado to gauge the impact of the country’s first-ever state law to tax and regulate the sale of marijuana to adults 21 and older. Since the first retail marijuana stores opened on January 1, 2014, the state has benefitted from a decrease in traffic fatalities, an increase in tax revenue and economic output from retail marijuana sales, and an increase in jobs, while Denver has experienced a decrease in crime rates.

Now, a new report from the Drug Policy Alliance brings another jolt of good news by providing comprehensive data on marijuana arrests in Colorado before and after the passage of Amendment 64 in 2012. The report compiles and analyzes data from the county judicial districts, as well as various law enforcement agencies via the National Incident Based Reporting System (NIBRS).

The report’s key findings include:

Since 2010, marijuana possession charges (not including Denver) are down nearly 80%, marijuana cultivation charges also dropped nearly 80%, and marijuana distribution charges are down over 97%. Of course, the number of marijuana possession charges in Colorado courts is where we saw the most overall decline in terms of sheer numbers of people no longer prosecuted.

According to raw data from the NIBRS, drug-related incidents are down 23% since 2010, based on a 53% drop in marijuana-related incidents.

In 2010 the top five counties for marijuana possession cases in Colorado were El Paso, Jefferson, Adams, Larimer, and Boulder. Marijuana possession cases in these counties all dropped by at least 73% from 2010 to 2014.

Marijuana distribution charges for young men of color did not increase, to the relief of racial justice advocates wary of a ‘net-widening’ effect following legalization. The black rate for distribution incidents dropped from 87 per 100,000 in 2012 to 25 per 100,000 in 2014.

Racial disparities for still-illegal and mostly petty charges persist for black people when compared to white people, primarily due to the specific increase of charges for public use combined with the disproportionate rates of police contact in communities of color. The marijuana arrest rate for black people in 2014 was 2.4 times higher than the arrest rates for white people, just as it was in 2010.

The report also reveals a decline in synthetic marijuana arrests, presumably because people are less likely to use synthetic marijuana when marijuana itself is no longer criminalized.

“It’s heartening to see that tens of thousands of otherwise law-abiding Coloradans have been spared the travesty of getting handcuffed or being charged for small amounts of marijuana,” said Art Way, Colorado State Director for the Drug Policy Alliance. “By focusing on public health rather than criminalization, Colorado is better positioned to address the potential harms of marijuana use, while diminishing many of the worst aspects of the war on drugs.”

“The overall decrease in arrests, charges and cases is enormously beneficial to communities of color who bore the brunt of marijuana prohibition prior to the passage of Amendment 64,” said Rosemary Harris Lytle, Regional Chair of the NAACP. “However, we are concerned with the rise in disparity for the charge of public consumption and challenge law enforcement to ensure this reality is not discriminatory in any manner.”

“What is often overlooked concerning marijuana legalization is that it is first and foremost a criminal justice reform,” said Denise Maes, Public Policy Director for the ACLU of Colorado. “This report reminds us of how law enforcement and our judiciary are now able to better allocate time and energy for more pressing concerns.”

In January, DPA released Marijuana Legalization in Colorado: One-Year Status Report. It found that since the first retail marijuana stores opened on January 1, 2014, Denver has benefitted from a decrease in crime rates, and the state has shown a decrease in traffic fatalities while increasing tax revenue, economic output and employment opportunities. Updated data reveals that the first year of legal retail marijuana sales resulted in $52.5 million in tax revenue (excluding revenue from licenses, fees and medical marijuana). Millions are allocated to fund youth education, drug prevention efforts and the improvement of public school infrastructures. In addition, the state is enjoying economic growth and the lowest unemployment rate in years.