One example would be a vandalism loss at an abandoned, run-down
property. The cause of the loss may be kids or vandals discarding a
cigarette. However, the property owner itself may be legally liable for that loss.
Another example would be the cause of the loss is a water supply line
failing, but the manufacturer of the fill valve or the plumber who installed it is legally liable for that cause.
There are many sources of discerning who is legally liable for a loss, such as legal treatises, cases, hornbooks, all of which are available at law libraries and in many insurance carriers offices. Your subrogation counsel is another good source.