I don't know how you come to this conclusion, but a guy who lives a few blocks from me was kicked off the police force for misconduct.
Getting kicked off of the police force is a far cry from "being convicted" and from what I have seen, even that is relatively rare as a result of their misconduct while on patrol. Generally speaking, that is the MOST serious punishment they get for any crime they get caught committing while on duty, whether there is hard evidence/multiple witnesses or not. In most cases they and/or their fellow officers can fairly easily fabricate testimony to "justify" any action they get caught taking.
The fact that you are unaware of this kind of thing shows how biased your information collecting skills are. Work on that.
That is hardly a fact. The truth is I have been following the Mehrsele case and, AFAIK, it is the first ever murder trial any officer in the country has ever received for his actions on duty (though there have been a number for their actions off-duty) even in cases where suspects were clearly shot in the back on video and at least one I know of where the suspect was shot for following orders and the shooting officer was caught changing his testimony at least twice (Elio Carrion Case). Much like Rodney King, the Mehrsele/Grant case is very likely only because of clear video evidence and national attention. Also much like Rodney King's assault, I doubt there will be any criminal conviction.
Also note that the officer seen clearly repeatedly punching Grant in the head without provocation (the same officer who was kneeling on his neck) had no charges filed whatsoever. Though he did eventually get fired, it was not until months after the incident occurred and, again, very likely that was due to national scrutiny (possibly in conjunction with other complaints).
Sounds to me like he said you have to bribe and be from a well connected family. He didn't say, "in some corrupt towns in the US." Is that really a statement you want to defend?
What he said is pretty much accurate. In many places you cannot even officially file a complaint. In quite a few officers try to threaten/intimidate complainers. Most DA's are completely unwilling to even bring charges against officers without VERY hard evidence because of work/gov politics and because it is difficult to convict when judges and juries nearly always side with officers over anyone else who. DA's rely pretty much solely on evidence collected by the officer in question and his colleagues. It is illustrated time and again that officers are generally unwilling to implicate their colleagues for anything they do. On top of it all, (and perhaps most significantly) admitting any form of culpability could implicate fellow officers as well as make the entire department susceptible to lawsuits for their training and/or policies.
All of these factors conspire (along with a few others) to make it near impossible to even get an officer disciplined, let alone held accountable criminally. Most of those factors are covered in the report mentioned above. While the comment I am defending might be a slight exaggeration, I think part of your problem is that you are prone to oversimplifying statements to read what you want. He is saying that it is very difficult for someone who has been unjustly treated by an officer to do anything about it in this country, especially if they are a minority, from out of town and have no money or political pull. This is pretty obvious given what he said and the context in which he said it.
The only part that even slightly conflicts with my own experiences and findings regards bribery because, AFAIK, that usually only works with the dirtiest of cops and usually pertains to ongoing criminal activity rather than withdrawing charges/tickets that have already been filed or disciplining any misconduct. While I will grant you that misconduct is less likely to occur in some places than in others, I'm pretty convinced that it exists in nearly every department in the country and nearly impossible for the average person to do anything about it in 99.999% of cases.