This is a sensitive subject for a lot of people, and I'm sure after I type and submit this experience, there will be several people with differing opinions to comment below. It is not my intention to offend anyone. This is simply my opinion, which I have a right to.
I believe that finding out the reasons behind people who commit crimes is key to preventing such crimes from happening again. Everything we do, we do for a reason. People who cheat, lie, kill, steal, people who abuse children or animals... they all do those things because of some mental illness or some trauma from the past they have never healed properly from.
I believe in due punishment, but I also believe in rehabilitation. Digging in and finding the root of the problem would help a lot of people who commit crimes (and those who don't commit crimes but still behave in unacceptable ways) to stop committing them and behaving this way. Maybe not every single case, but statistics show great numbers of criminals who never return to prison after they complete rehabilitation programs. I think that says a lot.