I really don´t remember the name, if anyone could help it would be amazing, any hint would help!

Scene I remember:

A woman marries a man, and when they leave the church, where they have married, the man gets killed by a shot from a gun. The shot comes from a window in a building nearby. Nobody knows what happened. The woman wants to take revenge and wants to kill those murderers. What comes out during the movie ist that the killers are friends and didn´t do in on purpose, it was just an accident, because they were like playing with a gun... that´s all I remember! Anyone a hint what it could be?