A senior garda has been suspended while a historical allegation of sexual assault is examined.

The investigation began after the alleged victim saw the Dublin-based officer on television.

Garda headquarters made the decision to suspend him while the allegation is investigated.

It is understood the officer denies any wrongdoing.

The Herald can reveal that specialist officers from a Divisional Protection Services Unit have been investigating the case for a number of weeks.

A senior source revealed that a preliminary file on the case – which is described as “very complex” – is at an “advanced stage” and that it is almost ready to be sent to the Director of Public Prosecutions (DPP).

The suspended officer was not a garda at the time of the alleged offence.

It is claimed he carried out a sexual assault on another young male during a “babysitting scenario” in the 1980s.

“The garda was a juvenile in his late teens when the alleged incident took place,” said a senior source.

“The male who has made the complaint was also a juvenile at the time. This makes it a very complex case.

“There is no CCTV footage, no forensic or mobile phone evidence, for investigators to use in the case, but detailed statements have been obtained.

“The allegation is of a serious nature and it was decided that the most appropriate thing to do in this case was to suspend the garda until the DPP makes a decision.”

The victim complained to the authorities after he saw the garda on TV.

Distinguished

The “highly sensitive” investigation has been ongoing since then.

It is understood that the suspect did not become a garda until a number of years after the alleged assault.

Sources said that the officer – who has not yet been arrested as part of the investigation – has had a “very distinguished career” with the force.

According to figures released by gardai, the number of officers suspended on suspicion of serious misconduct has almost tripled since 2016.

Twenty-one officers were suspended last year pending criminal investigations or internal disciplinary inquiries. This was up from nine in 2017 and eight in 2016.

Not included in these figures are three officers who have been suspended as part of a high-profile investigation into corruption.

The three officers – who include a superintendent an inspector and a senior detective – were arrested in May in high-profile raids.

The arrests were part of an investigation led by the National Bureau of Criminal Investigation (NBCI) and the Drugs and Organised Crime Bureau (DOCB).

The appointment of Garda Commissioner Drew Harris last September has led to an increased focus on discipline within the force.