I had the same issue with a guy in a silver BMW, he would open his door when i would ride between the cars during traffic jams, every morning same place, same time.
This would cause me to brake heavily, as i reached his car he would close his door just in time. Until i stopped next to him, leaned into his window and said. "The next time you do that i'm going to the police." He didnt do it again.
Like Taha says, it doesnt matter, just report him before he hurts you.
