A Labor-dominated Senate inquiry is investigating whether Dutton misused his discretionary powers as immigration minister to grant visas to two European nannies against the advice of his department.

Dutton stepped in to free one young woman from immigration detention in 2015 after his office was contacted by AFL chief executive Gillon McLachlan.

He also saved from deportation an Italian au pair who was apparently planning to work for a former Queensland police colleague.

Dutton allowed the two young women into the country on tourist visas.

Appearing at a public hearing into the high profile visa decisions, Home Affairs secretary Michael Pezzullo confirmed he had asked the police to investigate leaked inter-departmental emails about the McLachlan case.

“In these circumstances, it’s obligatory on a secretary to make reference to the federal police, and that’s occurred in this case,” Pezzullo said in Canberra today.

The border boss suggested there may be a criminal investigation into the email leak.

“Document transmission is traced down to the level of printing, down to the level of transmission to external accounts,” he said.

Pezzullo refused to answer questions about the documents.

McLachlan will give evidence via teleconference to explain his involvement in lobbying Dutton to overturn the deportation of the French au pair.

Alexandra Deuwel was detained at Adelaide Airport in October 2015 after admitting she intended to work in breach of her tourist visa for grazier Callum MacLachlan, the AFL boss’ second cousin.

MacLachlan contacted his relative, who directed his government relations guru Jude Donnelly to forward an email from Callum MacLachlan to the minister’s chief-of-staff.

The quick intervention has triggered suggestions of “mates helping mates”, but Liberal senator Eric Abetz suggested criticisms of Dutton’s speedy response were bizarre.

“I would have thought we should all be celebrating that the department and the minister can make quick decisions rather than keeping somebody in detention unnecessary,” he told the committee.

Peter Dutton has used his ministerial discretionary powers to grant more than 4129 visas since assuming the role in December 2014.

But as few as 14 of these relate to tourist visa interventions, like in the cases of the two au pairs.

“These powers build flexibility into an otherwise highly prescriptive visa process,” Pezzullo told the hearing.

Department officials confirmed no compliance work was done to see whether the au pairs were abiding by their visa conditions, but both young women left the country on time.

Dutton has consistently denied any wrongdoing in both cases, saying he had no personal link to anyone involved.

– AAP