How do you avoid prosecution? Being in possession of child pornography is a crime. If you personally identified these torrents, then you are essentially confessing.
There is an interesting story in "Three Felonies a Day" where an employer discovers child pornography on an employee's computer. They contact their attorney, and the lawyer deletes the offending contact to protect the company. He then alerts authorities to the employee. The attorney is eventual prosecuted for evidence tampering. It's an absurd Catch 22.