The man accused of killing a federal agent during a road-rage confrontation earlier this week may have a good self-defense case if the agent threatened him, legal experts said Friday.

The two men had exchanged obscene gestures after Wonder pulled in front of Pettit in traffic, police say. Wonder was apparently in a hurry to get to an appointment for kidney dialysis.

After the angry exchange, Wonder, who does not have a criminal record, pulled into the parking lot. Pettit, a 52-year-old retired Army officer, drove around the corner and went into the parking lot from a separate entrance. Both men got out of their cars.

After a brief exchange, police said, Wonder shot Pettit in the head.

The nature of that exchange will be at the heart of the case against Wonder. Florida’s Stand Your Ground law, passed in 2005, allows someone to use lethal force in self-defense if he or she fears the other person is about to kill or cause ``great bodily injury.’’