Matt Canavan leaves two properties worth more than $1m off 2019 declaration of interests

Paul Karp and Amy Remeikis
Photograph: Mick Tsikas/AAP

The Nationals senator Matt Canavan omitted two properties worth more than $1m from his current declaration of interests, declaring “nil” interests in real estate despite owning two houses in Yeppoon, Queensland and Macquarie in Canberra.

The former resources and northern Australia minister – who quit last week to support a bid by Barnaby Joyce to return to the Nationals leadership – has claimed he was not required to declare the interests in the 46th parliament because he had already done so in the 45th.

But the registrar of senators’ interests, Rachel Callinan, told Guardian Australia that “senators are required to declare the interests that they hold as at the relevant date”, a fact which suggests that Canavan misinterpreted advice to senators.

Related: Canavan delayed releasing documents about coal lobby interactions before resigning

On his register of interests dated 29 July 2019 Canavan declared “nil” interest in real estate despite disclosing a “mortgage on investment property” with the Commonwealth Bank as a liability on the same declaration.

A title search conducted on 5 February in Queensland reveals that Matthew James Canavan is the joint owner with his wife, Andrea Johanna Canavan, of a property in Barmaryee (outside Yeppoon), which was bought for $555,000 in November 2017.

In the Australian Capital Territory, the couple owns a long-term leasehold expiring in 2067 on a house at Macquarie, which sold for $499,500 in January 2009.

Canavan did disclose the two properties as recently as 20 February 2018 in an update to his register of interests for the 45th parliament, declaring the residential property at Macquarie and the Yeppoon house as his principal place of residence.

That disclosure was prompted by a report in The New Daily that he had missed the deadline to declare the four-bedroom, two-bathroom home outside Yeppoon, which he blamed on “an inadvertent administrative error”.

A spokesman for Canavan claimed the Department of the Senate had advised “the Senator was not required to declare any interests that were declared during previous parliaments”.

The spokesman quoted advice from the registrar of senators’ interests on 24 June 2019 drawn from the senators’ handbook. It required senators to provide “details of benefits received since your last notification of alterations of interests, as well as your interests as at the date of the first meeting of the Senate after 1 July following a general election”.

The registrar of senators’ interests referred to the same section to support the opposite conclusion, explaining it meant “senators are required to declare the interests that they hold as at the relevant date”.

On Tuesday, a spokesman for Canavan would not commit to seek clarification or amend the declaration.

According to parliament’s website, senators must disclose “the senator’s registrable interests” within 28 days after the first meeting of the Senate after 1 July first occurring after a general election.

Any senator who “knowingly provides false or misleading information to the registrar of senators’ interests … shall be guilty of a serious contempt of the Senate and shall be dealt with by the Senate accordingly”, it says.