檸檬大俠不是報稅專家，估計他也幫不上啥忙。得問有關專家。進一步搜索，發現這和國家報稅政策的變化有關

Theft Losses

The IRS defines theft as "the taking and removing of money or property with the intent to deprive the owner of it. The taking of property must be illegal under the law of the state where it occurred and it must have been done with criminal intent.” 

 

Again, beginning in 2018, the theft must have occurred due to a presidential disaster area declaration. In 2017, you might have had a theft loss if you were the victim of blackmail, burglary, embezzlement, extortion, kidnapping for ransom, larceny, or robbery.

So how would this work under the terms of the TCJA? Let's say that a hurricane strikes your hometown, and the president declares that it's a disaster area. But, miracle of all miracles, your vintage car sustains only minimal damage because it was tucked safely away in a garage that was built to withstand hurricane damage.

All is well and good...but then a thief takes advantage of the fact that one of the garage windows was broken in the storm. He's able to gain entrance and make off with your car. The theft and the disaster were related so you might possibly make the argument that the theft was deductible.

https://www.thebalance.com/casualty-and-theft-losses-3193002

 

俺的理解是，當前必須是雪上加霜的情況下，才能報theft loss.