What could possibly go wrong?
1. Overcrowding in female prisons.
2. Underutilized male prisons.
3. Rape epidemic in female prisons.
Just a few possible things, I'm sure there's more.
Actually if you are male and straight and a criminal that wants to be locked up with females it could be pretty good! If I get to keep my junk.
Personally I approve of this program on the basis of the prisoner voluntarily having a testicle and penile removal first. This will drastically cut down on the number of requests.
The prisoners that will endure or desire this have earned the right to be with the girls. Those that will endure such will have their asses kicked by the girls. It is a win win.