Stonewalling on Houston and other things we didn't learn on Right to Know day

Labor’s Senate leader Penny Wong has blasted officials for stepping around questions about whether Scott Morrison’s office attempted to have the Hillsong pastor Brian Houston attend a state dinner at the White House.

Officials from the prime minister’s department and the finance minister, Mathias Cormann, stonewalled during a Senate estimates hearing on Monday, declining to answer questions about Houston and the dinner on the basis the answers could be prejudicial to international relations. A series of questions were taken on notice.

Wong was at pains to point out the refusal to disclose basic factual information – a pattern repeated across several estimates hearings on Monday – came on the same day that Australia’s media organisations unleashed the Right to Know campaign against moves by successive federal governments to penalise whistleblowing and, in some cases, criminalise journalism.

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Morrison has refused for weeks to answer repeated questions from journalists and in parliament about whether he tried to get one of his religious mentors on the guest list for the invitation-only Rose Garden soiree but was ultimately thwarted by the White House. That development – never denied by the prime minister – was revealed first by the Wall Street Journal while the prime minister was on his American visit.

A riled Wong told the hearing: “I think the public has a right to know whether our prime minister asked for Mr Brian Houston to go to the White House.” She declared Morrison should be “frankly man enough and brave enough to answer the question”.

Departmental officials told the hearing they had not supplied any suggestions to the White House for guests for the state dinner, but declined to answer whether or not Morrison’s office had made suggestions, offering a formulation about answers being potentially prejudicial.

When the official answering the question, Gerard Martin, indicated his answer to the question had been prepared after “discussions within the department”, Wong suggested his non-answer had been coached.

PMC deputy secretary Stephanie Foster said officials always prepared themselves for estimates hearings, including for instances where answering the question could prejudice international relations. Wong queried how answering that question could prejudice international relations, and Cormann intervened.

Last month, Guardian Australia filed a freedom of information request with the Department of Prime Minister and Cabinet for documents and communications related to the state dinner and Brian Houston.

The statutory response date was due to be Wednesday, but less than an hour after officials shut down questions about the dinner in Senate estimates, an FOI officer within the department emailed seeking a 30-day extension on processing the request because “regrettably, the department is not currently in a position to finalise the decision on the FOI request.”

In addition to Monday’s skirmishes over Houston, officials from Morrison’s department told the hearing they could not provide information about who was the official point of contact within the government for the Barr investigation – a controversial probe established by Donald Trump aimed at discrediting the Mueller inquiry.

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Trump phoned Morrison just before his visit to Washington to ask for a point of contact within the government to cooperate with the Barr probe – a fact revealed first by the New York Times and later confirmed by Morrison. Officials from the prime minister’s department told estimates on Monday they were not on the call.

Justin Hayhurst, from the international division of PMC, told the hearing he had been verbally briefed about the substance of the call after it had taken place by someone in Morrison’s office, but had not made a note of the briefing.

After a line of questioning resulted in it remaining entirely unclear who the designated point of contact was, Cormann told the hearing the first point of contact was Australia’s “outstanding and distinguished ambassador” Joe Hockey. He said he would take Wong’s inquiries on notice.

Cormann also accused Wong of “participating in an international leftwing conspiracy” of trying to suggest there was something untoward about Australia agreeing to participate in the Barr inquiry, when there was “nothing remarkable about it”.

Wong rejected that characterisation, and insisted she was seeking factual information.