Loosely speaking, In order to prove adultery, you would have to have physical evidence of the spouse with his/her girlfriend/boyfriend. For example, you could provide the court with photos of them together (not standing side by side persay but more romantically involved), testimony from witnesses that have seen them in romantic situations, love notes, cards, or some tangible documentation from one to the other. That said, you can also hire a private investigator to follow your spouse, but that is not inexpensive. Also, divorce rates really depend on the attorney that you go with, its hard to give a price range as no one knows how long your case will take.
Proving adultery can be an expensive undertaking. It also can exact an emotional toll in addition to what you may already have been through.
If you have a low income and the marital assets aren't significant, it may not be worth it to prove adultery. Even if there are substantial income and assets involved, adultery is not always a factor in determining equitable distribution and support in PA. For some purposes it is only one of several factors that might impact the financial aspect of divorce. You should consult an attorney to determine if it would be beneficial to prove adultery in your case. Even if you do prove adultery, will it be worth it in the end, or are you being motivated by some other need?
In PA, the no-fault divorce statutes exist to help people go their separate ways when the marriage has broken down. You should consider if those statutes can help you get the divorce you want so that you can move on in your life in a way that is cost-effective and efficient.
The price a divorce attorney might charge varies and is typically dependent on the facts of the case and the amount of work involved to achieve your legal goals. Your attorney should be forthcoming about his/her billing rates and practices. Most attorneys charge by the hour, but some prefer to use fee-based arrangements (like I do) if they can. Again, if you choose to file a fault-based divorce claiming adultery, you need to consider how doing so will increase your legal fees for a possible court hearing or trial.
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