Of course cops can lie. But is unlikely they'd tell such a stupidly big lie as this. It is also unlikely they'd all lie in sync, with government and media collusion. While the world will always be round, regardless of what people thing, if enough people tell me something happened such and such a way, and without evidence to the contrary, I'll tend to listen to them than the few voices on the fringe. Otherwise, I'd be a Holocaust denier.