[Jazzy3113]

1. In a hit like this, the less time Michael had the gun the better. If he tried to dump it somewhere, he could seen before or after, someone could see him do it, etc. Also, he was going to be taken out of the country that night, so it would be very difficult to ID him. Also, he wasn't a criminal at that point so his prints would not be on file and he would not be around for them to compare prints.

Basically, by leaving the gun there police cannot find it somewhere else and try to tie it back to the family. They had witnesses that an italian man shot those two, they have the murder weapon and thats it. No excuse to bother the family now.

Even recently in organized crime hits the guns are left at the scene of the crime, but they almost always use gloves. You see if you take the gun with you and for some reason do not dispose of it or leave it somewhere, like your car/house, and the police find it you will be an accessory to a murder.