If a person is on 1st degree felony deferred adjudication, but would like to hire a private investigator (to inform the wife of the man the ex cheated with of his infidelity) is this illegal or breaking any type of laws that would violate the probation status of the defendant in the state of Texas?

There is currently a no harmful or injurious contact order between the alleged victim and the defendant. And the defendant would be the one to hire the private investigator.

It could be argued that it's harmful. Mainly it's incredibly stupid every which way from Sunday.

It could be illegal if the cheater dude and your ex had anything at all to do in your adjudicated felony. Did they? If this is just as it appears revenge against your cheating ex and the guy she cheated with it could still backfire and get your probation jeopardized as an unrelated consequence of a bad act.

If my first case is true, then using a third party to screw the guy (or your ex) would be highly illegal and a violation of your order of non harmful or injurious contact. If your looking to add to your court problem then revenge is a good a way as any.

The other guy has nothing to do with the case, but I think I will advise my friend that it is a bad idea.

Very bad idea, I will assume, (you really are vague on info) but one of the two parties must have either been a co defendant or a victim that caused the person to be charged with the crime. And I also assume he has been ordered to no contact.

But he is still filled with hate and anger and wants to still get even. This can be viewed as an indirect contact, and even part of an ongoing activity.

In Texas, the DA office if there was a complaint about this, could easily see this as a violation.

Remember it does not have to be a crime, just a violation (non criminal) behavior that can cause it to go back to court