The PC investigated the former boss due to an alleged grudge

A police dog handler detained his former boss on suspicion of drink-driving because of a grudge, a misconduct hearing was told.

Avon and Somerset PC Lee Umpleby chased Sergeant Steve Knight’s car for five miles on May 14 last year before he persuaded traffic officers to pull him over and breathalyze him in what proved to be negative.

PC Umpleby told the hearing that Sgt Knight, his former line manager at the Ministry of Defense (MOD) Police, was a “bully” who he believed had driven him drunk in the past.

PC Umpleby admits misconduct but denies serious misconduct.

Monday’s hearing at Avon and Somerset Police headquarters in Portishead was told that PC Umpleby had resigned from the Ministry of Defense Police in Corsham, Wiltshire, because he could no longer work with Sgt Knight.

It is alleged that after joining Avon and Somerset Constabulary, PC Umpleby, who was based in Almondsbury, South Gloucestershire, ‘engineered’ the roadside stop.

PC Umpleby denied it was “payback” for his former boss who refused “excessive” mileage claims, leading to a disciplinary finding of misconduct against PC Umpleby following an internal review of his expenses.

He said he arranged for the car to be stopped because he feared someone might be killed, either on the way or through Sgt Knight’s role as a firearms officer, the Local Democracy Reporting Service reported.

But barrister Louise Ravenscroft, representing the force, said: “PC Umpleby had no reliable or credible evidence or any information to suggest that Sgt Knight might be drink driving.

“PC Umpleby used his position as a police officer to pursue a previous complaint he had with Sgt Knight.”

PC Umpleby said the pair clashed because they disagreed with the way Sgt Knight was running the station and added: “He was a bully and used that to intimidate other officers.

“I challenged him on this several times, which he ignored and denied.”

The hearing was told that when PC Umpleby resigned from Corsham, he left a copy of a letter to the Ministry of Defense chief constable for his colleagues to see, criticizing Sgt Knight, who he called it “character assassination”.

“It wasn’t character assassination, it was an attempt by me to justify to everyone why I was leaving,” PC Umpleby said.

PC Umpleby claimed he saw his manager drunk at work twice on weekend shifts but could not report it because it would cause problems for colleagues and the only way to catch him was breathalysing.

He said: “On reflection I shouldn’t have turned up at the scene but I would always stop at a traffic stop to support colleagues.”

Body-worn camera footage showed Sgt Knight telling traffic officers at 05:00 BST that his last drink was at 22:30 BST the night before.

PC Umpleby said Sgt Knight should not have been drinking alcohol because of Ministry Police rules for officers with firearms.

He added: “I could have done things differently, but it was the right thing to do.”

PC Umpleby also denies obtaining unauthorized information about his former sergeant’s shift pattern, failing to tell Avon and Somerset Police about their previous association and also failing to file an intelligence report.