Michael Harker accepted the allegation that he ran an account on the social media platform now known as X while serving as a constable in Cumbria Police.
A misconduct hearing was told he had resigned from his post following the discovery of the account, which was reported to the force’s professional standards anonymously.
The former officer ran the illicit account under a pseudonym, linking a payment app to enable him to sell explicit material involving a man on the platform.
He was later identified as the publisher of the images, thanks in part to the anonymous reporting, Cumbria Police said.
It was also alleged ahead of the hearing that he had failed to disclose the account as a business interest.
The former officer was found to have committed gross misconduct and was dismissed without notice.
Despite his resignation, he will be entered on the College of Policing’s barred list for ‘wholly inappropriate’ behaviour described as ‘out of keeping’ with Cumbria Police’s ‘ethics and values’.
The hearing was chaired by Chief Constable Mark Roberts, of Cheshire Constabulary, who said the dismissal was ‘necessary in order to protect the public from a police officer who so clearly lacks the integrity and standards required of the role’.
He added: “In my opinion, this was gross misconduct which does undermine public confidence in policing as well as the particular reputation of Cumbria Constabulary.
“A lesser sanction than dismissal would not serve to uphold high standards and deter misconduct that is so completely out of keeping with colleagues’ and the Constabulary’s ethics and values.
“Furthermore, importantly a dismissal is necessary in order to protect the public from a police officer who so clearly lacks the integrity and standards required of the role by barring his re-entry from the profession.
“In terms of the outcome that most appropriately fulfils the purpose given the seriousness of the conduct in question, it is clear to me and it is my decision that the imposition of a final written warning would be a wholly inadequate outcome for behaviour of this kind and therefore that nothing less than dismissal would fulfil the purpose of the police misconduct regime.
“I make clear that such conduct shall not be tolerated by the police force.”