Looking back through history can show us how developing the police into the form they are today has done a lot for society and created a safer environment within cities and urban cultures. There are systems in place, a variety of checks and balances to prevent the corruption that can naturally develop in any office that provides power. They do a lot of good, and I believe that many people are drawn into that form of service out of a desire to do good and make the world a safer place.
However I think it's naive at best to assume that the corruption which has been well documented in past decades is over and that our system is finally perfect. While it's great that the police make things better for most of the people most of the time, it's hard not to worry when you see that the exceptions to that are statistically biased by race. This doesn't mean that any individual officer or case, regardless of those involved, exhibits racism but as a broad trend we know with quite measurable accuracy that there is a problem there.
On a personal level, you should treat police the same way you should treat anything. Assess the personal risks to yourself, evaluate their likelihood and take whatever reasonable precautions will reduce your risks without causing more problems than they solve. In most areas, as best we can tell from the numbers available, running into major problems with the police isn't a common risk. Under most circumstances it shouldn't be your most pressing concern and you'd probably get a greater safety benefit from something like being careful with your automotive maintenance. So unless you expect to have a lot of risk factors in dealing with police it's best to just take small precautions, such as keeping good records of any dealings you have with the police or crime, being aware of your basic legal rights and having a rough understanding of the way police work both in theory and in practice. Doing some of the things people have suggested, such as addressing the police with respect regardless of situation are likely to reduce risk. Taking a moral stand that this is an inappropriate demand is potentially quite valid, just be aware that unfortunately you may experience a personal cost for taking this moral stance. This is unfair but something you should be aware of to make an informed choice.
On a societal level we need to continue addressing problems within the police force and identifying ways in which policing can be improved. We need to look at things like the hiring practices, what forms of oversight occur, the growing militarization of US police forces, disparities in treatment of minorities and the way the legal code and sentencing applies to society. There are no really simple solutions in a complex developed society but hopefully in time we can find ways of improving all these things.