Christopher William Dove was initially charged with misconduct in public office over allegations he had failed to charge the suspect so he could make "sexual advances towards her".

The 32-year-old was due to face a District Court trial on Monday but prosecutors agreed to drop the misconduct charge on the condition Dove plead guilty to the lesser charge of neglecting his duty.

The case was then sent down to the Local Court.

Dove's barrister Kellie Stares told Downing Centre Local Court on Wednesday her client was working alone and without a paddy wagon on Melbourne Cup night 2013, when he pulled a 26-year-old female driver over for a random breath test at Fairy Meadow.

Police facts tendered to the court show the woman failed two breath tests and Dove "had a duty to arrest her and convey her to a police station, for the purposes of a breath analysis".

But the court heard Dove didn't have a vehicle available to take the woman in, and when his calls for back-up went unanswered, Dove made the decision to drive the young woman home.

What followed was an 18-month saga through the courts that ultimately led Dove to quit the force and move to Melbourne "for a fresh start", Ms Stares said.

Deputy Chief Magistrate Christopher O'Brien said that although he found the offence proven, he would dismiss the charge with no conviction recorded.

"You provided 10 years plus of service to the community of NSW," Mr O'Brien told the officer-turned-personal trainer.

"No doubt you have given a lot to the community ... You have punished yourself in many senses for your neglect on this occasion."

He said the fact that Dove had been charged and had gone through the court system "is sufficient to reflect the objective seriousness of the offending overall".

Tearful family members embraced outside the courtroom after learning Dove would go free with no criminal record and no fine. AAP