It's one of the most frustrating things drivers encounter on local four lane highways: people hanging out in the left lane and slowing down traffic.
It may be discourteous, but it's also against the law.
"Four lane highway, the law is drive right, pass left," said Pa. State Police Trooper Rob Hicks. "It's a little bit of courtesy and a little bit of safety."
Some drivers using Interstate 81 Wednesday afternoon expressed frustration with the left-lane loungers.
"Ninety percent of the people out there got the mentality nowadays they got to be in that left lane no matter what," said Oscar Donlan, a truck driver from Vermont.
"Left lane's supposed to be for passing," said Ken Eddy of Syracuse, New York. "Everybody's out in the left lane, but the minute you move over to the right lane, you shouldn't pass them on the right, but you try to get by them and they speed up."
Police said they do notice this happening.
"Yes, you do see that pretty often and across the state," said Trooper Hicks. "Last year, the troopers cited about 2,300 drivers for this particular violation."
Trooper Hicks said it's not safe when two vehicles are going side by side on the highway at the same slow rate of speed.
"That prevents the drivers who want to go the speed limit from doing so. That causes road rage incidents and crashes," Hicks said.