A South Australian MP has accused the state’s ICAC of corruption. 

SA Best MP Frank Pangallo has launched an attack under parliamentary privilege on the state's anti-corruption watchdog, the Independent Commission Against Corruption (ICAC).

Mr Pangallo says he has never seen more corruption within a government agency, accuding the ICAC of abuse of power and corruption in its handling of several high-profile investigations.

Mr Pangallo - a former Today Tonight journalist - alleged the ICAC knowingly pursued a high-profile public servant despite being in possession of evidence that showed he had done nothing wrong.

He also told parliament that documents had been doctored before being submitted as evidence.

“If I was still a journalist, this scandalous abuse of power and public money would easily top the stories I've done spanning 46 years. It's that bad,” he told the Legislative Council under parliamentary privilege.

“I have not seen this level of dishonest and corrupt activity within a government agency, let alone one dealing with corruption.

“They [ICAC] think they're untouchable. Protected - or so they thought - by the secrecy clauses that were built into the Act designed to protect the integrity of their investigations. Not for them to also be abused, as we now know has occurred.”

He has called on the State Government to establish a special inquiry into ICAC and the Office of the Director of Public Prosecutions (DPP).

Mr Pangallo’s allegations focused on two high-profile ICAC probes into former police officer Doug Barr and former Renewal SA boss John Hanlon.

Mr Hanlon was charged with abuse of office when the commission was headed by Bruce Lander and his prosecution, handled by the DPP, was dropped last week after a District Court judge dismissed evidence against him.

Mr Barr took his own life amid an ICAC investigation.

The crossbench MP spoke for over an hour, detailing information from what he said were affidavits, memos and documents linked to the ICAC probe into Mr Hanlon, who was accused of using taxpayer funds to go to Germany to visit his family.

Mr Pangallo said Mr Hanlon was working and not visiting his family, but phone data proving this had been held by an investigator before they left for Germany to interview people for the case.

Mr Pangallo alleged that the data was doctored and used as evidence against Mr Hanlon.

“It was only discovered late in the piece, on November 4, after a subpoena had to be issued,” Mr Pangallo said

“Why was it not discovered earlier? It was doctored evidence.”

Current Commissioner Ann Vanstone has committed to a review of the investigation into Mr Hanlon.

Ms Vanstone says she will “have something more to say” after the examination when she has discussed her findings with the ICAC reviewer, the Honourable John Sulan KC.

“Meanwhile, if Mr Pangallo has evidence that persons within ICAC are guilty of corruption then he should report that to Mr Sulan immediately,” Ms Vanstone said.

“I understand that Mr Pangallo is tabling evidence from the Hanlon brief in the parliament.

“Parliamentary privilege is there for good reason. It can shine light on darkness.

“But I hope that in using it Mr Pangallo will table the entire brief so that the public will be able to have the whole context of this matter.”

ICAC and the DPP have reportedly provided reports to Attorney-General Kyam Maher about their involvement in the matter.