It’s hard to say with any accuracy. Police corruption happens in the shadows, and the very people normally charged with rooting it out, the police, have an enormous incentive to look the other way and say, “Nothing to see here, move along.” Look up the Blue Code of Silence.
But certain countries pop to the top of the list whenever the topic is discussed. These include the United States of America, Russia, Ukraine, Brazil, India and Mexico. Feel free to exclude any of those you don’t feel are 1st world—another hard definition to nail down. I’d guess it’s safe to assume that where one fines that much smoke billowing up all the time, there just may be a fire.
Oh, and welcome to Fluther, @NewWorldSurvivor.