Colorado voters approved a constitutional amendment in November 2012, making it the first American state to legalize recreational marijuana. Since January 2014, when the residents began legally buying marijuana, a billion–dollar–a–year legal marijuana industry has emerged (expected to surpass $1 billion in sales by November 2016).

Did legalization cause marijuana abuse to skyrocket? Or did marijuana legalization actually work? The just-released Colorado Department of Public Safety report shows how legalizing recreational marijuana has affected Colorado. Here’re the key findings:

• The total number of marijuana arrests decreased by 46% between 2012 and 2014 (12,894 to 7,004). Marijuana possession arrests, which make up the majority of all marijuana arrests, were nearly cut in half (–47%). Marijuana arrests that were unspecified, meaning the specific reason for the arrest was not noted by law enforcement, went down by 42%.

• In terms of court filings, the total number of marijuana–related filings declined 81% between
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