By Dominic Giannini in Canberra

MIKE Pezzullo has been sacked as head of the home affairs department after a code of conduct breach finding.

Mr Pezzullo was stood down after a text message scandal, with leaked messages revealing the secretary repeatedly inserted himself into the political process.

The governor-general in council terminated his appointment on Monday.

The texts revealed he lobbied for his department and pushed his personal views, in breach of public service standards, over a five-year period.

It is not suggested the messages show corrupt or illegal conduct but public integrity advocates have alleged Mr Pezzullo overstepped the required impartiality.

Home Affairs Minister Clare O’Neil referred the matter to the Australian Public Service Commissioner after concerns were raised following the media reporting of the messages.

Lynelle Briggs was appointed to head the inquiry and has found he breached the code of conduct on at least 14 occasions in relation to five overarching allegations.

The allegations included that he used his duty, power, status or authority to seek to benefit or advantage himself, engaged in gossip and disrespectful critique of ministers, failed to maintain the confidentiality of sensitive government information, failed to act apolitically and failed to disclose a conflict of interest.

Veteran bureaucrat Stephanie Foster will continue to act as secretary until a new head is found.

The text messages showed Mr Pezzullo using a political back channel to get the ear of two former prime ministers through Liberal powerbroker Scott Briggs.

He suggested some ministers be sacked and which MP should oversee his department.

The texts showed he wanted Peter Dutton, now the federal opposition leader, to become home affairs minister.