In this case involving Gary Lee Colvin, the court allowed $780 as a business deduction for auto use. Colvin claimed $6,033 on his tax return, but he was missing that critical mileage log to prove his business use.

The court had this to say about the auto deduction:1

Automobile mileage deductions are subject to the strict substantiation requirements of section 274(d).

The court will not grant a deduction to the taxpayer who proves business use but fails the heightened substantiation requirements of ... Log in to view full article.