I don't care what country I'm in, I don't want an officer that's so quick to slip into casual racism as a "joke" "protecting and serving" me. Period.
McDonalds: "If I could spit in your order, I'd do it."
Doctor: "If I could inject you with AIDS while giving you your physical, I would."
Police: If I could shoot you with my gun, I would."
I'm sorry, it just doesn't fly, joking or not, and I'm not going to feel comfortable relying on your "service." The underlying problems of racism in any country are that the minorities being subjected to the racism, casual or overt, have been dehumanized by the group in power. Black people are often viewed as less than animals even, and it's no surprise when the excuses start to fly to give racists the benefit of the doubt, but with a minority, in particular a black man...well, "you grow corn you get corn."
I'm not cool with casual racism, and I shut that shit down real quick when I see it. Especially now a days.
Something else that bugs me is that people love to point out, "the black dude is laughing too, so it's all good!" In the past, I've let a lot of casually racist jokes slide because I was the lone black dude surrounded by my white "peers," that all laughed it up, and thought I was being "unreasonable" for pointing out that casual racism isn't cool or acceptable. "It's just jokes, bro!"
God forbid if those peers were cops. I'd laugh it off too. What else can you do? Minorities are often trained to overlook casual racism. Women are often trained to overlook casual sexism. That doesn't mean we're fucking cool with it. Not by a long shot. We laugh at your bullshit, but we are side eying the fuck out of you.
This black dude laughing at the cops "joke" means diddly squat. Having been in many uncomfortable situations in the past where I've had to swallow casual racism, I am intimately familiar with the "laugh it off" tactic of not rocking the boat. If you've never experienced casual racism directed at you, it may be hard for you to understand how not cool that shit really is.