A BID for justice by Ian Humphrey's wife has failed as the legal profession refuses to expel his killer.

An emotional Di Gilcrist-Humphrey has called the Legal Practitioners Conduct Board an "old boys' club" that made a judgment to let McGee remain registered.

"This decision is incomprehensible," she said yesterday. "This decision leaves the Legal Practitioner's Conduct Board with my husband's blood on their hands."

McGee hit and killed cyclist Ian Humphrey on Kapunda Rd in 2003, fled the scene and evaded police before handing himself in hours later.

He was set free by the courts and Ms Gilcrist-Humphrey appealed to the profession's watchdog to expel McGee for unprofessional conduct.

In a determination letter released yesterday, the Board ruled that the conduct did not warrant punishment as it was "not of an infamous nature".

Ms Gilcrist-Humphrey and Independent South Australian Senator Nick Xenophon have demanded the Board's sacking and called on the State Government to review its operations.

Mr McGee yesterday refused to answer questions about the ruling when leaving the Adelaide Magistrates Court after representing a client in a separate case.

Attorney-General John Rau refused to comment on the ruling, but said the Government was reviewing laws surrounding registration and regulation of legal practitioners.

Ms Gilcrist-Humphrey and Senator Xenophon were welcome to provide a submission, he said.

"Any reasonable person has some compassion for anybody who loses a loved one, and I obviously feel that compassion for Ms Gilcrist-Humphrey," Mr Rau said.

Senator Xenophon said the Board's ruling was "disgusting" and it should be forced to consider the public interest and reputation of the profession in future deliberations.