A New South Wales police officer has pleaded guilty to making a threatening phone call to Australian Greens senator Sarah Hanson-Young.

Sean Daniel Murphy, a Senior Constable, was charged with one count of using a carriage service to menace, harass or offend last month, after police searched his home in south-west Sydney.

At the time of the arrest, Senator Hanson-Young said the call was one of a number of threats she received during the debate over comments senator David Leyonhjelm made about her.

She said it was particularly distressing because the phone caller mentioned her daughter.

Mr Murphy did not appear in court today, as he is currently being treated for post-traumatic stress disorder in a mental health facility.

Barrister John Davidson said his client had worked as a police officer for 36 years and won two awards for bravery.

He said Mr Murphy has worked on the streets in Sydney, in "troubled areas" like Kings Cross, the inner city and Redfern.

Barrister John Davidson said his client had nearly lost his life in the line of duty. ( ABC News: Jonathan Hair )

"After 30 years on the street, he's seen more blood and mayhem than anyone can imagine," he told the court.

"He's nearly lost his life trying to save that of another.

"He has been described as being a victim of 'assault of police' some 200 times.

"After 30 years of serving the community … saving members of the community … he's now answerable to that community."

Mr Davidson told the court Mr Murphy was appalled by his conduct, which involved alcohol.

He said the 56-year-old had tried to arrange a meeting with Senator Hanson-Young to apologise, but the offer was declined.

Mr Davidson entered a plea of guilty on behalf of his client, who will be sentenced in February.

His bail was continued on the condition he lives either at the mental health facility where he is currently receiving treatment, or his home.