Green MP Jeanette Fitzsimons has been labelled "naive" for meeting with a group who claims that the collapse of the World Trade Centre in 2001 was an inside job.

Fitzsimons met Richard Gage, founder of Architects & Engineers for 9/11 Truth, in Wellington yesterday.

Gage has toured the globe arguing that a conspiracy of US government and big business colluded in the September 11 attacks and demolished the Twin Towers with explosives.

Fitzsimons said after her meeting with Gage that there were "some unexplained matters".

"What I've found is that there are a lot of highly trained people who say [the Twin Towers] could not have collapsed the way they say it did."

Asked if she was a 9/11 sceptic, Fitzsimons said: "I would say I've got an open mind. I'm not interested in conspiracy theories, I'm interested in evidence."

Matthew Dentith, an Auckland University PhD candidate who is writing his doctorate on conspiracy theories, said Fitzsimons' meeting was "naive" and would add credibility to groups with fringe and anti-semitic agendas.

"You want politicians to have ethical standards and who judge things with reason - and all the 9/11 conspiracies collapse when prodded."