How will putting this man in prison for a long time mitigate the complex trauma that the children have suffered? If he goes to prison for life, will it lessen their trauma?
The problem is that he will be free to offend again. The longer he is off the streets the safer people are, and not just children. And please don't think that the law and social services will protect against that; they should, but sometimes they won't, and sometimes they can't.
I agree that abusers can't be kep in jail indefinitely, but the longer he is in jail for - and the mother too - the longer people are safe. Because some people aren't safe, but aren't criminally insane either. If you have a better solution I'll love to hear it because god alone knows we need something.