A Hamilton police officer pleaded guilty to charges of deceit, neglect of duty and insubordination at a Police Services Act hearing Friday.

Const. Mason Murphy had been charged with five offences under the act.

He pleaded guilty to three charges, two other charges were withdrawn.

The charges stem from an incident on Dec. 31, 2010.

According to an agreed statement of fact, at around 7:30 p.m. that day, a woman and her husband were walking in the area of 701 Queenston Road when a car reversed and struck the woman, causing minor neck and back injuries.

The vehicle sped off, and the husband took down the plate for police. Murphy was the officer on the scene, and located the owner of the vehicle, who said her son had been driving.

The son was not present to be interviewed.

In February 2011, Murphy's staff sergeant instructed him to interview the man who was believed to have driven the car because the woman who had been struck asked about the investigation.

Murphy submitted an electronic form that indicated he had done the interview, but, in fact, did not make any attempt to speak to the driver.

"These misconducts are very serious and demonstrate a staggering lack of judgment and character," said prosecutor Marco Visentini. "A conviction of deceit strikes at the very heart of credibility and trustworthiness."

Visentini said the charges also diminish Murphy's credibility when being cross-examined in court cases.

The insubordination charge stems from improper note taking on Feb. 26, 2011. His entries weren't in chronological order, and there were no entries at all from 6 p.m. until 8:21 p.m.

Visentini said though there were no entries, he was doing work at that time, citing tickets to a cyclist that had been issued in that time period.

"There is no doubt in my mind he was on active duty," Visentini said.

Murphy has worked with Hamilton police for 12 years and has faced disciplinary action before. In 2005, he received a one-year demotion in connection with an assault.

Murphy's defense lawyer Pamela Machado acknowledged that incident, but said it "does not demonstrate a pattern of similar behavior."

"The public can have faith that Constable Murphy has learned from this incident," Machado said, adding that he has received eight commendations from Hamilton police in the past.

She also brought up an incident in June 2010, when Murphy saved a child's life. He gave CPR to an 18-month-old girl who was choking and "basically breathed life back into her," said acting Staff Sgt. Chris Willis.

Both the defense and the prosecution asked for a demotion from first class constable to second class constable for 18 months.

That works out to a $19,000 salary loss.

The hearing judge will release a decision by Oct. 26.