I know of one case where a divorced brother wanted to date a sister but the elders said he couldn't because he was still "scripturally" married due to his former wife (not a JW) not having remarried. The brother knew that she was sleeping around but couldn't prove it, so he and an elder staked her house out for a few nights until they saw a guy go in with her about 10 or 11pm and then leave the next morning. That was his proof. He was then considered "free to remarry" and was given permission to date the sister he liked.How pathetic is this story? A grown man couldn't go out on a date with a grown woman because some group of men said he couldn't. And then this grown man has to get someone to sit in front of his former wife's house to prove to them that guys visited her overnight.
That story is very similar to my son's. His ex-wife admitted to her affair, he tape recorded it, played it to the elders, but they said that wasn't enough evidence--because she denied the affair when talking to the elders. So another elder talked my son into going with him to stake out her house. They got the evidence, but it turned out it wasn't necessary because the ex-wife finally confessed.
Five years later our son finally found the right girl--she was also divorced. The elders wouldn't take her word that she was scripturally free ro remarry. They had to get a signed letter from her parents that they knew for a fact that her ex-husband was living with another woman.
Thankfully, our son and daughter-in-law are out of the "truth" now, and these events helped them along.