You know what the first rule of Police Fight Club is? You don't want to join it. Yes, even in this day and age of The Distributed Panopticon and multimillion-dollar lawsuits, there is no amount of money that will bring back the teeth you grew yourself, or make a broken bone heal any faster. If you want to fight 'em, hold your tongue, hold your temper, bide your time and hire a lawyer. You won't make as much money, but you'll still be alive to count it. Remember the maxim popularized by Chris Rock, among others: "If the police have to come after you, they're bringing a beating."
It would be nice if this weren't so. It'd be nice if government and civil service jobs were entirely filled by cool, wise philosopher-kings,* too, and while we're at it, how about a cookie? But that's not how it works. In the real world, these jobs are filled by the same range of slobs you find in any other line of work. Most are okay. A few are jerks. However -- and here's the critical distinction -- while most everyday encounters are on or very nearly the same level and a determined (or at least stubborn) person can expect to prevail much of the time, this does not hold when you interact with police. One of you has "sovereign immunity;" one of you has a radio to summon lots of armed help, backed by the full force and might of city, county or state government. It's not you.
Does anyone "have a beating coming?" Under our legal system, no; under the common custom and morality or our time and place, no. Not ever. If they do have "something coming," that's for the courts to decide, not the cops. But alas, Johnny Law has a limited range of options, all of which he is allowed to use if circumstances merit, and only one of them is "gentle persuasion;" every one of the remainder involve some level of force.
After the fact, it may not be justified; or it may be a lawful use of force that still rankles the popular perception. Maybe it's an outrage to be followed up by a week of riots. But someone has, nevertheless, suffered a beating. You don't want to be that guy.
Want to stop this? Get more cameras on more officers, in every sense of the phrase. Write your legislators. Boycott airlines that offend you. Wave signs, raise hell! --Just don't argue it out in the heat of the moment, because in that situation, there is no strategy that can result in you winning. Remember there is one human constant: Police will
respond to force with force and it is inherently disproportionate. You can whup 'em in the courts; you can beat 'em in the media; you can run 'em ragged in City Council or the legislature. By the side of the road, in an airliner seat, on a sidewalk...? Not so much.
* Based on experience, I'm starting to think these Platonic creatures are like unicorns and the Easter Bunny. Never met one. Don't believe I ever will.
N.B.: I'm going to get some pushback in the form of people accusing me of saying folks ought to knuckle under to jackbooted thugs. No. Wrong. What I'm saying is choose your ground; fight in venues where you've got a fair chance of winning.