The Queensland Parliament's ethics committee will investigate whether a Palmer United Party (PUP) representative offered inducements to Gold Coast MP Michael Hart.

Mr Hart, the LNP Member for Burleigh, says he was asked what the PUP would need to offer him to switch parties.

Police have already looked into a complaint from Mr Hart and say they will take no further action.

However, the Speaker has asked the ethics committee to investigate whether an inducement was offered, which would be a contempt of Parliament.

Mr Hart says when a PUP official approached him last month, "alarm bells were ringing loud and clear in my head".

"What was said was 'what can we offer you to come across to the Palmer party', which I took that as an inducement and immediately reported that to the police."

Mr Hart says he contacted Premier Campbell Newman about the issue.

At that time, PUP's Queensland leader and Gaven MP, Dr Alex Douglas, said that while Mr Hart was asked to switch parties, no inducement was offered.

Earlier this month, PUP founder and federal MP Clive Palmer served defamation papers on Mr Newman over the Premier's claims that Mr Palmer had tried to "buy" the State Government.