[craigharley]

According to the Bureau of Prisons, there are 207,847 people incarcerated in federal prisons. Roughly half (48.6 percent) are in for drug offenses. According to the Bureau of Justice Statistics, there are 1,358,875 people in state prisons. Of them, 16 percent have a drug crime as their most serious offense. There were also 744,600 inmates in county and city jails. (The BOP data is current as of July 16. From BJS, the latest jail statistics are from midyear 2014, and the latest prison statistics from year-end 2013.) That’s an incarceration rate of about 725 people per 100,000 population.

Looks like for federal prisons it's as high as 48.6%, but that looks like it's for all drugs not just cannabis.

It's also probably too big a leap to speculate how many people are incarcerated for drug related incidents (theft to get money to feed a habit for example). Crimes which would probably be greatly reduced in a treatment over prohibition system.

[wccrawford]

Your quote says that 16% are in with drugs being their most serious crime.

48% include drugs as a crime, but 2/3 of them have a more serious crime as well.

So I'd say the parent is right that 16% are in for drugs and would be set free if drugs were legal. The others in that 48% wouldn't be.

[mbrameld]

I wonder how often the more serious crime wouldn't have been charged had the drugs not let to it? For example, carrying a firearm isn't necessarily illegal, but carrying a firearm and weed in a place where weed is illegal is most likely a separate, non-drug charge like "carrying a firearm during the commission of a crime". Also how many non-drug arrests would have never happened if the officer hadn't been able to manufacture reasonable suspicion by simply saying, "I smell weed".

[PurpleBoxDragon]

The 48% is about federal prisons, the 16% is about state prisons. Generally the 'bad' crimes we think of (murder and the like) are state offenses, not federal offenses, which is why you see so many more in the state level for something worse than drugs. Drugs is one of the few crimes punished consistently on both a state and federal level. You could go to federal prison for murder, but it generally requires something special about the case for the state to not handle it.

>So I'd say the parent is right that 16% are in for drugs and would be set free if drugs were legal. The others in that 48% wouldn't be.

Both would be set free. 16% from state prisons, 48% from federal prisons. These are two separate prison populations.