That is a cellphone case sticking out of that person's back pocket.
Here's the rest of it, out of the pocket and up to someone's ear.
The photos initially started making the rounds last week, after the Ocean County, New Jersey, Prosecutor's Office posted the images on Facebook. It's been shared more than 14,700 times.
"Please folks – this cell phone case is not a cool product or a good idea," the office wrote. "A police officers' job is hard enough, without having to make a split-second decision in the dark of night when someone decides without thinking to pull this out while stopped for a motor vehicle violation."
Steve Linders, public information coordinator with the St. Paul Police Department, told BringMeTheNews they haven't heard of any situations where it's led to confusion or issues, "but we're certainly aware of them." He said they're not "commonplace," but the department is seeing them more than before.
They're easy to get a hold of, usually priced at about $10 or less and available on popular sites such as eBay and Amazon. Black, white and pink seem to be the most common colors available.
One website, wackydot.com, advertised the case as a "sexy pistol protective shell for iPhone 6 with unlimited times to pull the trigger." The item is no longer listed, however.
Other police departments comment
Since Ocean County officials weighed in last week, a handful of police departments around the country have taken to social media and said basically the same thing: don't buy one.
"This cell phone case is a terrible idea," the New Jersey State Police wrote on Facebook. "Officers do not have the luxury of time when making split-second decisions, while interacting with the public. We strongly recommend that you do not use this product both for your own safety and the safety of law enforcement officers."
For St. Paul officers it's part of their training, Linders said, as they make sure police are aware items like that are out there and in people's hands.
"We haven't had an issue with them so far, and hopefully it stays that way," Linders said.
Rochester Sgt. Dan Monnet told KAAL there's no law against the cases – but "common sense" says it's "probably not the most suitable cellphone case to be carrying around."
There don't seem to be any publicized cases of an officer mistaking the case for a gun, resulting in something bad happening.
But officials seem to want to get out in front.
"If he tugs on that pistol grip, we're going to assume it's a gun," Sioux City, Iowa, Police Chief Doug Young told the Sioux City Journal. "That's the scary part. ... You could have something tragic happen. It just puts us in a situation that we don't want to be in."
Alabama's AL.com collected and published reaction from law enforcement agents. One quote, from Pleasant Grove police Lt. Danny Reid:
"I can think of no worse idea for a phone case. Why would you want to make yourself look like a threat? And just by answering your phone you'll look like you have a gun to your head. Wow. Bad, bad idea. This will get someone shot in record time."