I'm afraid you are spot on. The fact prison most of the time makes people worse (truth be said it does act positively for some people sometimes, albeit rarely) is almost irrelevant here. I think the real problem is how the society at large clusters ex-convicts in a certain moral bucket, ad vitam eternal, when they are out. The idea that they have paid their debt to the society is ... just an idea in reality, and sadly, when they are released, the real punishment begins and makes them pay in all kinds of senses.
Firstly, I know it's not an easy subject with no perfect solution, and perhaps I'm a bit radical, but I think the very concept of rehabilitation will always just be a total joke as long as there is a culture of 'public records'. Especially in this google age. Nowadays, discriminations is getting less and less popular in this country, except towards ex-convicts, that's an open bar right there.
Secondly, disproportionate punishments. I mean, your case is such a perfect illustration. Ninety days in jail for possession of small quantities of drugs for personal use. And as you said with quotes, it was a "deal". Honestly, being an immigrant to this country myself, I'm probably not very well placed to criticize or comment that kind of realities of the justice system but to be honest, I often wonder whether or not people actually realize it's totally out of this world insane, and that very few others places on this planet would have justice systems inflicting such crazy punishments. I kind of suspect most people are in favor of those punishments actually, sometimes just culturally with a moral compass still a bit reminiscent of puritanism, and sometimes based on the belief that harsh sanctions can provide deterrence. One candidate in the last presidential election attempted to pitch the fact that 1.5% of Americans are behind bars as one issue to talk about, but it didn't seem to tackle much interest.
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