The Metropolitan Police has arrested a Conservative MP on suspicion of “indecent assault, sexual assault, rape, abuse of position of trust and misconduct in public office,” according to a force spokesman.

“In January 2020, the Met received a report relating to alleged sexual offences having been committed between 2002 and 2009,” he said.

In an updated statement released today, the force said the man, who’s in his fifties, had been released on bail “pending further enquiries to a date in mid-June.”

But, as FactCheck has covered before, you won’t find the arrested MP’s name reported in any major news outlet. Nor will their identity be released by Parliament, the Conservative party or the police.

Here’s why.

Why hasn’t Parliament named the MP?

It used to be that if an MP was arrested, the Commons Speaker would have to tell the House – either in an oral statement or by “laying” a letter in the House of Commons Library. This meant the arrested member’s identity quickly became public knowledge.

But in 2016, the rules changed at the recommendation of the House of Commons Standards Committee. The Speaker is no longer obliged to tell the House of a member’s arrest, and can only do so if the MP agrees.

The Committee’s rationale was that the previous arrangements were incompatible with a person’s right to privacy under the European Convention on Human Rights and other elements of UK law.

They said they wanted to bring the rules around naming an arrested MP in line with standard practice for naming an ordinary member of the public in such circumstances. Official guidelines say that police will only name an arrested person if there’s an exceptional reason to do so, like a threat to life.

Why hasn’t the Conservative party named the MP?

A Conservative party spokesperson told the BBC on Tuesday: “The Chief Whip [who is in charge of party discipline] has asked that the MP concerned does not attend the Parliamentary Estate while an investigation is ongoing. Until the conclusion of the investigation we will not be commenting further.”

Why hasn’t the media named him?

Once someone’s been arrested, the rules around what can be published are very strict. The idea is to make sure that if a case ever reaches a court trial, future jurors will not be prejudiced by what they’ve read or seen in the media.

In May 2020, the Court of Appeal endorsed a previous ruling by the High Court that said, “in general, a person does have a reasonable expectation of privacy in a police investigation up to the point of charge”. That case involved the news organisation Bloomberg, which had wanted to report the name of a businessman identified in documents relating to a bribery investigation. The Court of Appeal decision was upheld by the Supreme Court in February 2022.

And the stakes are high. Publishing something that turns out to be incorrect could result in libel action from someone who was wrongly accused, or even a conviction for contempt of court if a judge thinks what was published might create a substantial risk of serious prejudice to the outcome of a trial. These rules also apply to ordinary members of the public, including on social media.