Superintendent David Taylor has retired from An Garda Síochána.
He was heavily criticised by the Disclosures Tribunal for his involvement in a smear campaign against whistleblower Sergeant Maurice McCabe.
Superintendent Taylor had been suspended from the force in the wake of the publication of the report.
Taylor has 30 years service in An Garda Síochána and he will receive his full pension.
The report found that Taylor, the former head of the Garda Press Office, and former Garda Commissioner Martin Callinan ran a smear campaign against Garda whistleblower Maurice McCabe.
Justice Charleton said: "Superintendent David Taylor spun a deceit that his boss, Commissioner Martin Callinan, with whom he was on the best of terms for all his time in the press office of Garda Headquarters, and Nóirín O’Sullivan, who he decided for his own bitter reasons he didn’t like and was not up to the job, were on the one hand composing, and on the other approving, derogatory messages about Maurice McCabe."
"The tribunal is convinced that he pursued a scheme that somehow evolved out of his cheek-by-jowl working relationship with Commissioner Callinan.
"Their plan was that there was to be much nodding and winking and references to a historic claim of sexual abuse while, at the same time, saying that the Director of Public Prosecutions had ruled that even if the central allegation did not have credibility issues, what was described did not amount to an offence of sexual assault or even an assault."