Home Affairs Minister Peter Dutton had admitted background checks can’t be conducted on every person entering Australia.

Irishman Patrick Farrell has been arrested over an alleged one-punch assault and an unrelated stabbing in Sydney.

But NSW Police Commissioner Mick Fuller has said the Irish national lied on his forms upon entering Australia and failed to disclose his prior convictions.

The 29-year-old served three years in jail for a man’s death in Ireland nine years ago.

Mr Dutton told Ray Hadley the sheer number of people entering the country makes it impossible to catch out everyone.

“You just can’t physically verify all of that information.

“When the police become aware of it, or there’s a tip-off from a family member, then the police will act and the Border Force officers will deport that person.”

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