I doubt that you had a "drug problem" at age 15---or at least that you had a serious enough drug problem to warrant incarceration in an in-patient (I use the term 'patient' loosely--very loosely), lockdown facility of any kind, much less one as brutal as Straight.
Sure, our parents may have been desperate---but they fucked up to have gotten to that point in the first place. If they swallowed the line that "only Straight could help" then they were ignorant of the truth and too lazy to find the facts, or at least seek out a second opinion. I wouldn't have an ingrown toenail removed with out a second opinion, and I sure as hell wouldn't send my kids off to some warehouse without getting one, no matter how "out of control" they were. The parents that plead "what else were we to do? You were out of control and soon to be dead!" are merely tryint to hide their guilt and complicity in the abuses we suffered. If they knew what Straight was and sent us there, they are abusers. If they didn't know what Straight was and sent us there, they are criminally negligent as parents. For a parent to subject a child to what we were subjected to is criminal, pure and simple. For a parent to buy into the lies that Straight's salesmen shoveled them is stupidity. For a parent to not investigate a program they are considering sending their kids to is criminally negligent.
I understand your desire to 'clear the air' between your parents and you, but you do yourself a disservice by not recognizing their complicity in the abuses we suffered. They were charged legally, if not morally, with ensuring our well-being until we reached adulthood, and by putting us in Striaght, they faileed miserably.