Jail for 'Spousebusting' private eye

A private detective who investigated unfaithful partners has been sentenced in a Sydney court to a minimum nine months' jail for posing as a federal agent.

The sentence surprised 28-year-old Brett Sutcliffe's lawyer, who had argued for leniency in the case, but saw his client handcuffed outside the court after the hearing and led off by police.

Downing Centre Local Court heard Sutcliffe was carrying out surveillance in a parked car at North Bondi last July.

When a 77-year-old woman asked him to move from a disabled parking space he said he was a federal investigator and later sent her a threatening letter saying she had interfered with an Australian Federal Police investigation.

The woman realised who he was six weeks later when she saw a television report on his company "Spousebusters".

Arguing for leniency, Sutcliffe's lawyer told the court his client had pleaded guilty at the earliest opportunity to charges of impersonating a Commonwealth public official and using the postal service to menace, harass or offend.

He also said his client would suffer financial hardship after his licence was cancelled.

But Magistrate Pat O'Shane, imposing a custodial sentence rather than a fine, said it was a serious offence.

And though Sutcliffe's lawyer said he had not engaged in physical intimidation, Ms O'Shane said Sutcliffe's offence was against an elderly woman and that the letter he sent was intimidating.

Ms O'Shane had previously ordered Sutcliffe to undergo counselling, saying the incident reeked of immaturity.

A copy of the letter he sent to Pauline English formed part of the fact sheet tendered to the court.

Sutcliffe displayed no reaction as Ms O'Shane handed down the sentence of 12 months' jail with a non-parole period of nine months followed by a good behaviour bond.

Sutcliffe has also been fined $5,000.