[alexriddle]

Most of the time we knew because people are generally honest and tell the truth. A few times where we had concerns we'd apply for a police report - even if someone will lie to their insurer, they rarely lie to the police in the heat of the moment when reporting the crime.

All that said, I can't recall many instances where the theft wasn't either breaking and entering, or entry through an open access point. As easy as lock picking might be, it's not a common burglary technique.