There undoubtedly are. However, does that make it a good thing? Erik seems to be implying that his stereotypes against police officers are sound in logic because he's had a few bad experiences, so he's grouping all cops under that misguided umbrella.
I don't exactly understand what your problem is. I'm saying that it is data point #1. Based on my bad experiences and what I see on some of these body cam videos, when a cop approaches me, I put my guard up and act differently than I would with the old lady on the train because one of them can and will shoot me if I do or say something that they perceive as threatening. Now, suppose the first thing that they tell me is "Just wanted to say that I like your shirt... I'm also a Celtics fan," well now I have data point #2 and my guard will drop and I'm sure we'll have a great time talking about the ECF. How is this confusing to you at all? It's just how I like to live my life as an intelligent being. Why waste any of my life experience?
During your experiences were you arrested and/or cited? If so, then I could understand why you have these preconceived notions since those situations are clearly unpleasant. Or have you had a situation where an officer responded to your home when you were victimized and took the time to hear you out, fill out a report, and be sympathetic to your mishap? Clearly both situations are different in nature and an officer will usually have a different approach when you're committing a crime and/or a traffic infraction than he would if you were being victimized.
Trying to bring up the body cam videos to validate your point is also pretty poor. There are literally thousands of daily police interactions and with it thousands of body cam videos, but you're basing this on few extreme examples, which is probably about .00001% of police encounters.
That would be akin to saying I put my guard up when a black person approaches me because one time a black person broke into my vehicle and I've seen a lot of video online in which they're armed and committing robberies. That's seriously what you're insinuating whether you realize it or not.
While Erik's response to police seems to be very conscious, the truth is that most of us respond to highly stressful situations in a less conscious, more impulsive way. I think all of us experience some measure of stress when pulled over by a police officer. However (at least for me), it is a manageable stress - my rational brain is still operating and I am thinking stratgically about the most effective way to respond. If I were a person who has had bad experiences with police officers (in any context), it is possible that the stress would manifests more intensely. In that case, my subconscious protective reactions might be activated and I may very well do something that willl appear to the police officer as either threatening or non-compliant. Fight, Flight, or Freeze in their various manifestations are most likely interpreted by a police officer as a sign that he/she (the officer) should be alert to potential danger -- then, of course, the police officer's history comes into play and potentially causes him/her to have a high-stress reactive response. Escalation ensues on both sides.
Example: Remember a year or 2 ago there was a shooting in Minnesota. The man was in the driver's seat and his girlfriend in the passenger seat. Her 4 year old daughter was in the back seat. A seemingly low-stress pull-over went awry and the girlfriend captured the aftermath of the shooting/killing of her boyfriend on her cell phone. Meanwhile the 4-year old watches her mom's boyfriend get shot/killed and shortly thereafter sees her incredulous and angry mother get handcuffed and arrested (later released - no crime).
Now imagine 15 years from now this little girl, now 19, gets pulled over. A police officer strolls up to the car and suddenly the girl is overcome by panic. Perhaps she doesn't even know why. The police officer notices a young black woman behaving strangely -- nervous, non-responsive to his requests. He raises the ante -- orders her out of the car. In her panic she leaps to the passenger door and attempts to get out and run. The officer responds.....
Sorry for the drama. Just trying to illustrate that the police officer and the person he/she is intervening with are both complex human beings -- both with their unique life experiences and both prone (perhaps) to reaciting to stress triggered in their subconscious. An explosive and dangerous outcome is possible.
Bottom line for me is that we can't expect all citizens to be "trained" in de-escalation. However, maybe we should expect that all police officers are. In my opinion, police officers should be good self-regulators and highly aware of their own stress triggers. They should also enter each intervention with a citizen with an understanding of how trauma-related stress manifests and be skilled in proactive and reactive strategies that are minimally likely to trigger escalated emotional responses. That said, there are circumstances that police officers will trigger emotion just by their presence. Again, this is something they should be aware of, trained in, and highly skilled in managing.