Sen. Bill Heffernan, who represents the ruling Liberal Party, was making a point about a relaxation of security at Parliament House.
The 71-year-old wheat farmer said he had "brought this through security: a pipe bomb." From a plastic shopping bag, he took out what looked like a pipe bomb and several sticks of dynamite taped together, as he explained how he used to blast tree stumps on a farm.
Heffernan is a member of the Finance and Public Administration Legislation Committee, which at the time was questioning Australian Federal Police Commissioner Tony Negus about routine police and security issues.
Negus agreed with Heffernan that there was nothing to stop someone bringing explosive ingredients into the building through security.
"Under the current arrangements, that is a risk, yes," Negus said.
Negus later told the committee that Heffernan had warned him that he would produce the fake bomb.
"I was satisfied that it was inert," Negus said. But senators had not been warned.
"I just hope you are not doing anything illegal to which we are accessories," committee chairman Ian Macdonald told Heffernan during his demonstration.
Before last week, virtually everyone who worked in Parliament House had to go through an airport-style metal detector and have their bags x-rayed.
Now the vast majority are not screened. Journalists, diplomats and some contractors are among the higher-risk minority who continue to be screened.
Senate President John Hogg said the security relaxation was partly due to budget cuts.
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