Lawyers acting for federal workplace insurer Comcare told the court in Canberra on Wednesday morning that bureaucrats should not be entitled to taxpayer-funded compensation as result of a "personal choice."

The case of a Canberra-based public servant, injured during a "vigorous" sex session in a motel room while on a work trip five years ago has now made its way to the highest court in the land.

Comcare is battling to overturn a Federal Court decision that the woman, whose name has been suppressed by the courts, was covered by the workers' compensation scheme when the injury occurred.

The bureaucrat suffered lacerations to her nose and mouth when a glass light fitting was pulled from the wall of the motel room as she had sex with a local man in the NSW town of Nowra in November 2007.

But Commonwealth Solicitor General Justin Gleeson SC, told six judges of the High Court on Wednesday morning that the sex was "in every sense a personal choice."

"The injury arose because of a choice by the respondent to use the hotel room booked by the employer as an occasion for a particular form of sexual activity that caused the light fitting to be pulled from the wall," Mr Gleeson told the court.

The barrister argued that the sexual activity was "just too remote" from the work duties the woman was sent to Nowra to perform for her to be liable to workers' compensation.

Mr Gleeson described the sex as "a private activity that's none of the employer's business and none of the employer's responsibility when it comes to compensation."

The hearing continues.