Fall Back and Kill — Dick Stivers

Do it legally! This was the order Able Team had been given when they were sent to stop a militant biker gang that had hijacked an armored truck, leaving three guards and two cops dead. The Able warriors join up with a Federal strike force and go against their own instincts when they're told to investigate and prosecute, not search and destroy. When it turns out the hijackers have another target--the President of the United States--Lyons and company decide that if they can't stop the killers with law and order, they'll have to fall back and kill!