Most drivers have seen first-hand the dangerous driving habits of others.
"Texting and driving. Looking out the window. Not really paying attention," points out driver Chris Miller.
However, Tri-State police say one of the most dangerous habits they've seen lately is one that drivers often can't see.
"In situations like this, if someone is shooting up heroin, you're not going to know that," said Covington Police Chief Spike Jones. "An officer arrives and finds someone with a needle stuck in their arm and have overdosed or passed out."
According to police on both sides of the river, addicts are driving into Cincinnati to buy heroin and then shooting up as soon as they get it. Then they are trying to drive home.
"Whenever you have someone high behind the wheel, let alone heroin, it's a dangerous combination," Jones said.
It's a situation FOX19 first told you about last year, when Michelle Conda was hit by a car while out riding her scooter on Harrison Avenue. Conda suffered life-changing injuries and only later learned from the police report that the driver who hit her "passed out due to a heroin overdose."
Across the Tri-State, police and first responders are finding accidents and cars parked haphazardly on roadways as the result of heroin overdoses by drivers.
In Covington, officers have begun to target areas where they've seen overdoses on the roads. Their goal is to put the brakes on a dangerous habit that's driving addicts to put others in harm's way.
"Especially when you've got some place to go or you have kids in the car. That's just not how it's supposed to be," Miller said.