Liberal MP Ben Morton of Tangney, WA has been scrambling to firm up his Aussie citizenship credentials after an unwanted surprise dropped out of his family tree.

In 2017, he declared both of his maternal grandparents were born in the United Kingdom, and he has "never been an Irish or British citizen, only ever Australian".  But as he went through some old family records over Christmas, he came across documents that contradicted his assertion about his grandfather.

"While sorting through these papers over the Christmas break we found a photocopy of a British passport belonging to my maternal grandfather," he wrote.  "His nationality was confirmed as 'British citizen'.  His place of birth however was listed as Dublin."

The Irish Embassy this week sent along confirmation that Mr. Morton is not an Irish citizen.  But the episode displays lawmakers' anxiety over section 44 of the constitution after so many careers were disrupted or even ended during the citizenship crisis of 2017-18. 

Morton entered his discovery in the citizenship register, set up in 2017 as a way of dealing with the specter of dual citizenship stalking Aussie lawmakers.  They're supposed to update it within 21 days if they discover new information.  This system has many critics, including Tasmanian independent MP Andrew Wilkie who is calling for an independent audit.

"I've argued from the start that the only way to bring genuine clarity to the citizenship status of federal politicians is for an independent auditor to examine everyone's background," Mr. Wilkie said.  "The revelation that Ben Morton has been entitled to Irish citizenship all along is a striking demonstration of the continuing need for such an audit."