Way more good than bad, from an in-house perspective. One thing I have learned, do not argue with the person with the gun, try to defuse it if you can. Police are somewhat like firefighters, they run in where others fear to go not knowing what they will find. You never know when a simple situation can escalate into a dangerous one. The worst situation for police is a domestic violence situation. Many times the victim can become the aggressor.
BTW, I worked in the jail, no guns allowed, but still big, strong angry people who can be on drugs/alcohol or both and very upset at being arrested and brought in. I saw 3 grown men not able to subdue "nicely" one out of control man. Or one officer have his index finger almost bitten off by a woman out of control on drugs. Or the guy who kicked the hole in the check-in desk, etc. These people were not being seen at their best at that time.
Then there are those that are not a credit to their profession. Those people deserve to lose their jobs and I have seen more than you think lose their jobs. I was not shy about bringing their flaws to the attention of the people who were charged to handle that.
I went over to one woman's house to help her clean it up and fix things. She was so happy, and I felt better than I ever had in the jw D2D work. I helped people find the resources they needed. I also saw many of my colleagues do the same. I worked with juveniles that came from situations similar to my own and tried to be the kind of adult that had helped me.
Unfortunately, we live in a world where bad news is more exciting to too many viewers and readers. Good people's deeds are too boring. Just my observations.