Proving adultery by reading emails, chatroom discussions

My sister in law found out her husband was cheating with her best friend by reading his emails when he passed out drunk and left his computer up. She later installed a "big brother" program to follow up. She has multiple emails from him to her best friends talking about their sexual escapades. Her lawyer first told her it was all admissible in court. Now tells her it cannot be used because she got it all without his knowledge. SOOOOO is there a loophole?? They use chatroom discussions and emails for pedophiles.

A concerned sis

[tbyte]

Why does she need it in the first place? Other than for herself?
Chances are they live in a no-fault divorce State, so there would be no need to prove infidelity.

Even if you live in a no fault divorce state you can prove adultery and use it but it will cost lots of time and money. Are their children involved. Are they having sex in front of the kids?????? My husbands ex cheated on him for 10 years and he didnt have the money to go forward with it. He had tapes of her on the phone with her boyfriend for hours every day. talking like a **** in front of her child and the courts and the childs guardian did nothing.