Zurich cantonal police raided Blocher’s home and offices on Tuesday over suspicions he breached bank secrecy rules when he passed on information relating to the former head of the National Bank, Philipp Hildebrand. 

Blocher said he deserved immunity since the data was only given to him in the first place because of his position within the National Council, newspaper Tages Anzeiger reported.

The controversial politician also maintained that his duties as councillor had prompted him to deliver the information to the then president, Micheline Calmy-Rey.

“If I had not been a National Councillor, I would never have done this,” he said.

He also insisted that he was the victim of a political conspiracy, and accused politicians of putting pressure on the Zurich prosecutor, online news website 20 Minutes reported.

This is not the first time that Blocher has sought to rely on parliamentary immunity from prosecution. In 1994 he got away with voting illegally on behalf of an absent colleague, and in 2001, he was protected after he made racist and anti-Semitic remarks, 20 Minutes reported.

The rules on immunity have only recently been tightened. They now require the action taken to “have a direct connection with one’s official position or activity”. It is unclear whether such a connection can be established.

The prosecution believes that no immunity applies, although prosecution spokeswoman Corinne Bouvard refuses to reveal what the precise arguments against Blocher having immunity are, as she says it would require the prosecution to respond to specific allegations.

Questions have also been raised as to whether the information that the case against Blocher was being extended served to tip him off to the possibility of the raids on his properties.

Blocher confirmed on Wednesday that his legal representative had been warned that the investigations were being extended but complained that information regarding the extension must have been leaked, since the news programme “10 vor 10” knew of the searches before they had taken place.

“It was agreed on Monday that absolute silence on the extension of the process would be maintained,” he said.

However, initial investigations showed that no information had been leaked to journalists either by the police or the Public Prosecution Office, spokeswoman Bouvard said.

Blocher also queried whether the search warrants were correctly obtained, as he believed that the warrant would have needed approval from the President of the National Council.

But such approval would only be required where an investigation had not yet been launched, a spokesman for the Federal Assembly told Tages Anzeiger.

Blocher received assurance on Tuesday that all the necessary paperwork had been obtained from Bern.