Random Riddle

The victim was in a convertible. He was shot when the top was down.
Hold your mouse over for the answer.
A man was shot to death while in his car. There were no powder marks on his clothing, which indicated that the gunman was outside the car. However, all the windows were up and the doors locked. After a close inspection was made, the only bullet-holes discovered were on the man’s body.

How was he murdered?