A man whose Scientologist brother committed suicide has urged Prime Minister Kevin Rudd to allow a parliamentary inquiry into the controversial church.

Thirty-year-old Edward McBride killed himself in the Brisbane suburb of Everton Park in February 2007.

Mr McBride had been a member of the Church of Scientology for about two years and had paid $25,000 for various courses.

A coroner's inquiry into his death heard evidence that members of the church had contacted him 19 times in the days before his death about completing an "audit".

The church's file on Mr McBride was subsequently sent out of the country to the US, meaning it could not be obtained by the Coroner.

His brother, Stephen McBride, last night flew from Perth to Canberra to urge Mr Rudd to support Independent Senator Nick Xenophon's motion for an inquiry into the church's tax-free status.

"It's hard to describe the anger that my family and myself feels about the church's conduct before and after my brother's death," he said.

"The Church of Scientology gained $25,000 from my brother, but Edward lost his life. This organisation needs to be investigated by the police and by the Parliament.

"I believe the bombardment of 19 telephone messages backed him into a corner and he just had no room to breathe. I think the secrecy of the religion, organisation, cult - whatever you may call it - it needs to be open and disclosed.

"There's something just not right about it. Please don't let my brother's death just be in vain."

Stephen McBride said he believed his brother became involved in the church after becoming bored with his job in the Army.

Edward McBride had complained of bullying in his Army work and the Defence Force has since conducted a commission of inquiry into the incident.

At the time of his death he was trying to leave the Army and was frustrated at the length of time it taking for him to be discharged.

Coroner John Lock found there was nothing to suggest the bullying and issues surrounding his discharge contributed to his death.

He also said some of the phone calls made by church members to Edward McBride in the days before his death were "virtually demanding" he come in to complete the audit.

The Church of Scientology has been under increased scrutiny since Senator Xenophon used parliamentary privilege to accuse it of being a criminal organisation last week.

Senator Xenophon, who detailed allegations of forced abortion and imprisonment from former members, says he does not yet have the numbers for an inquiry, but will not be giving up.

"I will continue to build my case," he said.

"My fellow senators need to know that even if a vote is lost, either now or early next year, there is nothing to stop me from putting up a motion the very next day for another vote on it."

Greens leader Bob Brown, whose party is backing Senator Xenophon's call, described Edward McBride's story as "terrible".

"If the Scientology cult has nothing to hide it won't be concerned about an inquiry," he said.

"There's a much wider issue here of religious conviction and the passage of money, large amounts of money."

The Church of Scientology has described Senator Xenophon's allegations as "outrageous" and false.