BRUCE SCHREINER
Associated Press

BARDSTOWN, Ky. (AP) — After a late-night shift, officer Jason Ellis was driving home when he had to pull his marked police cruiser over on a highway exit ramp and remove tree limbs blocking the road. When he got out of his car, authorities say someone ambushed him, shooting him multiple times with a shotgun.

A year later, his slaying is still unsolved, something that is rare in the U.S. Nearly all of the more than 900 officer killings during the last two decades have been solved, according to the FBI.

In Ellis’ case, authorities have not released many details. They won’t say whether anything was taken, or if the debris put in the road was intended to stop Ellis, any officer or just a random car.

“No one called anything in, nor did he call out on anything,” said Bardstown Police Chief Rick McCubbin. “It was as routine and ordinary as it comes.”

From 1996 to 2012, more than 900 law enforcement officers were intentionally killed, according to the FBI. Only 16 of those slayings have gone unsolved, including eight in the U.S. territory of Puerto Rico, the FBI said.

One reason behind the high success rate is the constant communication between officers and dispatchers, said Bill Doerner, a criminal justice professor at Florida State University. Police gain valuable information from the back-and-forth, something that didn’t happen in the Ellis case because he had signed off after his shift ended about 2 a.m.

“An officer on a traffic stop has already radioed in the location of the stop, tag and vehicle description,” he said. “Similarly, officers who are attacked after they have responded to a call … have already advised dispatch that they are on scene.”

Plus, when an officer goes down, there is usually a strong response from all of law enforcement.

In another unsolved case, a police officer in Maywood, Illinois, was shot multiple times as he sat in his vehicle on a residential street in 2006.

Valdimir Talley, police chief of the western suburb of Chicago, believes Tom Wood’s killing was linked to his work on drug cases.

Wood’s grieving colleagues got their arms tattooed with Wood’s badge number. As the years passed, hope for catching his killer hasn’t faded.

“Criminals sometimes make mistakes,” Talley said. “We’re waiting for that one lead.”

Ellis and other law enforcement officers killed in the line of duty during the past year were remembered at a candlelight vigil Tuesday night in Washington, and at another ceremony Thursday.

In Bardstown, a town of some 12,000 about 40 miles southeast of Louisville, shops lining the quaint downtown still display pictures of Ellis, along with inscriptions referring to him as a hero.

Tips have poured in and police dangled about $200,000 in reward money and billboards publicized the case, but there have been no major breaks in the case.

Police questioned people arrested by Ellis, a K-9 officer, and investigators asked residents to contact them if they had trees trimmed or removed from their property around the time of the slaying.

The lack of an arrest is frustrating, but investigators remain confident they’ll solve the case, said Jeff Gregory, a state police spokesman in the Elizabethtown post. An investigator is assigned to the case full time, Gregory said.

“To us, it looks like an ambush, somebody that put some thought into it,” he said. “So it’s going to take some thought on our part to figure out who that person or people were.”

McCubbin, the town’s police chief, thinks someone in the Bardstown area had a hand in the slaying.

The makeshift memorials to Ellis on display in shop windows are “the community’s way of telling whoever is involved, we’re not going to forget,” he said.

Since Ellis’ death, his canine partner, Figo, was retired from police work and is living with Ellis’ family.

Bardstown residents came together this week for a ceremony remembering the man known as a tough, dedicated officer with a soft side, especially for children.

During drug raids where children were present, Ellis “would be the first one, after we were secured, to start comforting kids, to get down and talk to them,” said Bardstown police Capt. Tom Roby. “You could always count on that.”

In a statement, Ellis’ widow, Amy, thanked the community for its “unending” support. She recalled a time when she didn’t think she could make it “through my next breath, let alone a year.”

“Please continue to remember us as we continue trying to put the pieces of our shattered lives together,” she said.

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