PHOENIX (3TV/CBS 5) -- Nobody likes to see the lights and hear the sirens, especially when you're the one getting pulled over.
But Valley streets and freeways have a seen spike in the past year in fake cops.
They make traffic stops on the freeway, following motorists at night.
One is even accused of trying to pull over an undercover state trooper.
That happened last year on State Route 51.
Police say Matthew Disbro was driving a vehicle that resembled an unmarked police car. He was wearing some sort of police uniform and activated red and blue police emergency lights.
"Law enforcement's more concerned about this than anybody because they're the ones out there trying to conduct business," Andy Anderson said.
The retired assistant Phoenix police chief says even well-meaning police wannabes can be a dangerous distraction.
They may feel like they're helping but directing traffic is dangerous - even for real law enforcement.
"Obviously, the one we are most concerned about is the one who is the predator," said Anderson.
Earlier this summer, Gilbert police released a surveillance video that shows a police impersonator pulling someone over under cover of night.
Police officers were looking for that driver.
You can find plenty of police-looking lights and sirens online, and it's easy for anyone to purchase.
Owning this stuff is completely legal.
Using it on the roadways is illegal.
Disbro is charged with impersonating a peace officer, but we learned that he was registered as a funeral escort driver. So, he's allowed to have those lights on his vehicle, just not to use them - unless he was escorting a funeral procession.