Almost all politicians (and people,for that matter) support the involuntary incarceration, imprisonment & treatment (behavior and thought reform) of underage youth. The difference is in how, and where they are placed. Democrats and those leaning to the left, toward government control, prefer that representatives of the state control the troubled teen industry. They want special kiddie courts, kiddie judges, kiddie prisons, and kiddie prison staff, the whole works. They want control over the entire system, top to bottom. From the low level staffers, to the top administrators, from the cook, to the psychiatrists... they all work for the state.
The republicans and those leaning toward the right, and individuality, prefer that families themselves make the decision when, if, and where to place their kid. They prefer to allow a free market of facilities, and let parents choose for themselves where to send their kid, assuming the parent knows better than some judge or some government bureaucrat.
The debate isn't that different than the debate over public education vs. privatized education. The democrats and liberals want state control over it all, uniformity, and all that. The republicans prefer a free market of schools, vouchers, etc. But what you NEVER hear anyone say, from anywhere in the political spectrum is that 'kids should not be educated'. They argue over where, and how to educate the kids, not whether education should happen or not. This situation also applies to the TTI. The politicians will argue about how the system operates, and where to place the 'troubled kids', but in reality it makes little difference to the kids whether they rot in a private, or public prison.
