A word to the unwise: What you post on your Facebook page could be used against you in a court of law—specifically, divorce court. Veteran family-law attorney David Littman now trawls the Internet more than ever before to glean evidence for his divorce cases.

And what does he find?

“A person can deny on the witness stand that they used marital funds to take a vacation with a girlfriend or boyfriend,” he tells 9News. “Well, lo and behold, photos show up on a Caribbean island.”

Attorney Cyndy Ciancio recently used Facebook to settle a case in which her client wanted to cease alimony payments because he believed that his ex-wife had remarried. The ex-wife denied the claim. But then up popped a picture on Facebook—an ex-wife with a new wedding ring and a baby, leading to a settlement.

The cases highlight the rising insecurity of personal information online, particularly on social networking sites, where someone might even be posing as “friend” but is really collecting private information.

In a report on the trend, The Associated Press reels off a long list of anecdotes, such as a husband who denied having anger management issues but wrote on Facebook, “If you have the balls to get in my face, I’ll kick your ass into submission.”

Then there’s the mom who denied in court that she smokes marijuana but posted pictures of herself smoking it.

As for Facebook being the cause of relationship or personal woes, that’s a stretch. As Helen A.S. Popkin writes for MSNBC, “Facebook doesn’t cause divorce–spouses do.”