According to The Economic Impact of Illicit Drug Use on American Society, last published by the Department of Justice in 2011, enforcing illegal drug laws imposes an annual cost on the American criminal justice system of $56 billion; while incarceration of drug offenders imposes an annual cost of $48 billion.

That's $104 billion spent annually by states and cities on two aspects of the drug war (and doesn't include treatment, public assistance, and a slew of other costs), compared to roughly $21 billion spent by the federal government. For $1.5 trillion to reflect just federal spending, the federal drug control budget would need to have been $37.5 billion a year, every year, for the last four decades. It's only slightly more than half that this year.

So, yes: There is a huge problem with the chart, in that 40 years of federal drug control spending does not add up to $1.5 trillion (though minus the "$1.5 trillion" in the middle of the image, the chart does accurately represent the growth of the federal drug control budget and the relatively flat rate of addiction to illicit substances). But even if the chart were designed to reflect "all costs associated with drug prohibition" over the last 40 years, with the right Y axis reflecting the growth of state and federal drug control spending, it would still be wrong, because $1.5 trillion doesn't nearly cover it.

Via Drugsnotthugs.com and Reason's own Cynthia Bell.

Update: A reader points out that the dollar amounts on the right Y axis don't add up to $1.5 trillion. The creator of the chart, documentary filmmaker Matt Groff, Tweeted the following in response to a question about where the $1.5 trillion figure comes from: "Short answer: chart shows only fed drug control, $1.5T refers to all costs assoc. w/ drug prohibition, blog on it shortly."

First off, I take the blame for not seeing the discrepancy. Shame on me.

But here's the funny thing: While the $1.5 trillion figure doesn't correspond to the numbers at right, it's actually low. In 2010, the AP put the 40-year tab of federal drug control spending at $1 trillion. But the massive federal drug control budget–for fiscal year 2013, it'll be $3.7 billion for interdiction, $9.4 billion for law enforcement, and $9.2 billion for early intervention–is actually a pretty small slice of the pie. States and municipalities have their own drug war expenses–investigating, trying, and locking up drug offenders–and those expenses actually dwarf what the federal government spends.

Update 2: Over at his blog, Matt Groff responds to concerns about his chart: