Thomas had been talking about seeing how a big department works, and Defibaugh extended an invitation after clearing it with his supervisors.
The night of Feb. 5, Thomas headed out wearing civilian clothes and the signature black cowboy boots that he wears on the job at home.
"The first thing they asked me was if I had a vest," Thomas said. "They meant a bulletproof vest. I didn't have one. They told me to bring one next time."
Thomas said he was impressed from the start, even with the officers' pre-shift roll call in which they get their assignments.
"It's just like it is on television," he said.
He was most impressed with the number of calls that came over during the shift.
"The radio never stopped talking," he said. "They must have had 200 calls. They were stacking up. There were so many at once that they told the officers to take two or three and pick their own priority. It's a lot different in Mercersburg. We get two or three calls on a busy Friday night."
Defibaugh said it was a typical night.
Another thing that left an impression on Thomas was how Montgomery County officers back each other up.
"Sometimes four or five cruisers showed up at an incident," he said. "We answer ours alone."
But Defibaugh said he sometimes answers 20 calls a night without backup.
Calls on the night Thomas rode with him included one for a kidnapping in which two parents forcibly took their 18-month-old baby from the foster home in which it had been placed.
"They took it out in the cold with only a diaper on," Defibaugh said.
They also answered a call for a possible suicide in progress in the basement of a home. That investigation included a check of the scene by a K-9 unit. Someone had heard a shot and called police. It turned out not to be a suicide.
That was followed by a call to a scene at which a man had been stabbed numerous times in the head and another to a domestic call in which the wife was beaten so severely she was taken away in a stretcher.
They were also called to an elementary school basketball practice where a 9-year-old player was assaulted by an adult.
"Mercersburg residents don't really understand how good they have things here," Thomas said. "It was like moving from 'The Andy Griffith Show' to 'The Jerry Springer Show.' I guess the biggest thing I learned is that I'm not going to move down there."
Defibaugh, who drives the 65-mile commute to Montgomery County, agrees. "Why do you think I live here?"