Former Tory chairman Jake Berry has alleged Suella Braverman made “multiple breaches of the ministerial code” when she was sacked as home secretary, before being dramatically re-installed by Rishi Sunak less than a week later.

Braverman admitted to a “technical infringement” of the rules as she was forced out prior to the downfall of Liz Truss, making her then the shortest-serving home secretary in history.

But Berry, who was sacked by the new prime minister on Tuesday, told Talk TV that there had been “multiple breaches” of the code, which sets out how members of the government must behave – or face punishment.

He said: “From my own knowledge, there were multiple breaches of the ministerial code.”

On Wednesday, Sunak told MPs that Braverman’s behaviour was just “an error of judgment”. Berry’s comments will raise questions over Sunak’s claims that his premiership would lead to “stability and unity”.

Braverman left her role in Truss’s cabinet after she was caught sending veteran backbench Tory John Hayes, a fellow right-winger, an official document from a personal email account.

She accidentally copied in someone she believed was Hayes’s wife, but was in fact an aide to Conservative MP Andrew Percy, who raised the alarm.

Braverman argued it was merely a draft written ministerial statement on immigration which had been due for publication imminently.

Allies said she sent it after going on a 4am immigration raid before coming clean about her “mistake”.

But officials said the file was sent much later and that the cabinet papers had first been forwarded from her ministerial account to a private Gmail account before going elsewhere.

Berry told TalkTV: “It was sent from a private email address to another member of parliament. She then sought to copy in that individual’s wife and accidentally sent it to a staffer in parliament.

“To me that seems a really serious breach, especially when it was documents relating to cybersecurity, as I believe.

“That seems a really serious breach. The cabinet secretary had his say at the time. I doubt he’s changed his mind in the last six days, but that’s a matter for the new prime minister.”

Braverman said she “rapidly reported” her “mistake” through official channels, and informed cabinet secretary Simon Case, as soon as she realised it.

But Berry said: “As I understand it, the evidence was put to her and she accepted the evidence, rather than the other way round.”

Labour has demanded that Case, who is reportedly “livid” over her swift return and “very concerned” about the breach, launch an investigation “into the extent of this and other possible security breaches”.

Keir Starmer has accused Sunak of doing a “grubby deal” to reappoint Braverman as home secretary.

During the brief leadership contest Braverman swung behind Sunak in what was seen as a blow to Boris Johnson’s hopes of staging a comeback to No.10