When a person is married and then decides to marry someone else secretly can he continue to stay married to both without ever caught by the law?

A friend of mine has been married for 12 years and they have two children. The husband decided to have multiple affairs and then one day met someone that he wanted to marry. He never told the young lady that he was still married. He told her that he was divorced, which was a lie. So They get married and they have a child. The first wife finds out that this has happened yet does not want to lose her husband or her family. She’s willing to forgive and move on. The second wife finds out that he’s actually still married yet refuses to leave him. Without someone telling the law about this situation is this something that can be found out by the law to incriminate the husband and the second wife? Asking for my friend.