No doubt you might know your son was a scumbag, but that does not mean that you would openly admit such a thing to the press. Right or wrong, Parents, loved ones, and friends of dead criminals will often only discuss the virtues of the dead criminal, or the potential good of the dead criminal as if the potential was the same thing as who the criminal is at the time he is killed.
After all, there is no way that the family will be able to win a wrongful death lawsuit against the police if the family talks about what a danger the criminal was to society.
Heck, even when such incidents are caught on tape where they show the officers operated within the law, within department protocols, etc., family members will still claim that the officers were in error, used excessive force, etc.
There was a case in Garland Texas a few years back about a teenager with a knife and causing mischief. His sister called the police because he had threatened her. The boy was shot and killed by the officer who arrived on scene. The whole incident after the officer's arrival was caught on audio and part was caught on the video. The boy approached the officer with a knife (maybe it was knives) and the officer drew his gun. The boy continued to approach and the officer repeated was yelling at the kid to drop the knife as the kid advanced on him. After several commands, the officer could be seen backing across the field of view of his dash cam, still giving orders. As I recall, the boy had backed the officer some 50 feet or more. As the officer is about to pass out of the field of view, the boy with the knives enters the frame. It is clear that he isn't more than six feet away from the officer who kept backing and giving commands to drop the knife. Finally, the officer shot the kid, killing him. With the exception of the sister who called 911, the entire family went on TV to tell of the great injustice to the boy and that the officer could have used other means to stop the boy. Based on the video, I thought the officer showed amazing restraint, if not almost to such an extent to have not been prudent to wait that long.