Why didn't they arrest Alex Pretti when he committed assault and destruction of property?

He committed an aggravated assault, destruction of property, and could have been charged in federal court for just having the gun during the commission of a violent felony.

So by now, most everyone has seen the video of Alex Pretti spitting on a police officer (aggravated assault), kicking the taillight off a truck (destruction of property) all while carrying a firearm. Apparently even someone legally able to carry a firearm can get a mandatory 5 years just for having a gun while assaulting an officer in any way. It becomes 7 years if they brandish the weapon.

Now the spitting thing is a bit tricky as someone had charges dropped for spitting on police officers. Apparently the judge in that case said that the spitting did not constitute a crime even though the law clearly suggests it does. But in a federal criminal court, we probably would not see that same sort of logic applied. Moreover, the law becomes more serious if you are spitting at an officer as part of any obstruction of any official law enforcement duty. If it is done in that situation, it is considered aggravated, which constitutes a felony.

So Pretti could have been arrested that day. Instead of being dead, he would have faced up to 15 years for the aggravated assault, up to 10 years for the destruction of federal property (assuming the damage was more than $1000), and an additional 5 years for committing the crimes while carrying a firearm. In theory, upwards of 30 years worth of potential jail time. But they let him go and less than two weeks later he was dead because he continued his nonsense, maybe because he thought he could continue to get away with it.