So, proactive police departments try to save lives by increasing their patrols. Greater visibility has an effect, as Officer John Christmas demonstrated Monday on State Route 50.
"You'll have one doing 55 mph," Christmas said, holding the radar gun while parked near the metal city line sign, but well within the city, according to a wooden city greetings sign.
"And then, they're doing 46 mph," he said. "You can see the car's nose go down" because of a sudden reduction in speed.
Clearly, even the drivers who obey the speed limit hit the brakes when they see a patrol car just off the road in what is so obviously a police officer enforcing the speed limit.
"But at night," he continues, "they don't see you until they're coming by because there are no street lights here."
Christmas speaks openly about his position near the Exxon gas station with the On The Run convenience store just down the highway at its intersection with Franklin Pike.
"Our officers will be out on heightened awareness patrol" during the holidays and especially on New Year's Eve, Police Lt. Rebekah Mitchell said in a telephone interview.
Mitchell is assigned to be the Lewisburg Police Department's connection with the Tennessee Governor's Highway Safety Office. Among its many services, it pays overtime wages for officers conducting sobriety checks and increased enforcement to encourage seatbelt usage; the Click It or Ticket program.
While sobriety checks -- normally performed in this area by the Tennessee Highway Patrol -- are not something city police will conduct this coming weekend, Mitchell said, "We're going to put extra people out there... It's a way... to, hopefully prevent a fatality."
It's also a way, she and Police Chief Chuck Forbis have explained, to reduce the risk of unnecessary grief.
"This is our mission," Mitchell said. We want to reduce fatalities."
She's well aware there are people who continue to feel pain long after the crash.
"It's hard anytime," Mitchell said, "but the effect on the family is worse when it's a young person" whose life's been lost.
Forbis has asked motorists and their associates to think ahead. Police do not like delivering bad news after a highway fatality, he said.
Mitchell cites statistics from the National Highway Traffic Safety Association. The bottom line is that there are more fatalities during certain times of the year.
Obviously, they include New Year's Eve. Like the Fourth of July, it's one of the times of year when city police become more proactive.
For the officer who enjoys the job -- to protect and serve -- it's like Christmas all over again.
"A while ago, a man came by at 81 mph in this 55 mph zone," Officer Christmas said in his patrol car Monday as he spoke of a case that's been to court already. "He fell asleep in the back of the car" after he was taken into custody.
It was one of those protect and serve moments at the city line.