What proof do you need?
For a theft loss, you should first show all of the following:
- When you discovered that your property was missing
- That your property was stolen
- That you were the owner of the property
- Whether a claim for reimbursement exists for which there is a reasonable expectation of recovery
Where can you deduct the loss?
If you have a theft loss, you can claim it on schedule A line 20, the same way you would be able to claim a casualty loss. A theft is 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 laws of the state where it occurred and it must have been done with criminal intent. You don’t need to show a conviction for theft. Theft includes the taking of money or property through fraud or misrepresentation if it is illegal under state or local law.