William Daniel Heffernan (born 3 March 1943),[1] is an Australian former politician who was a Liberal Party member of the Senate representing the state of New South Wales from September 1996 to May 2016.

In September 1996, the NSW Parliament appointed Heffernan to replace Liberal Senator Michael Baume, whose resignation created a casual vacancy.

[7] In 2007 Heffernan was appointed Chairman of the Prime Minister's Taskforce to examine the potential and opportunities for further land and water development in Northern Australia.

"[12] The Senate Standing Committee on Community Affairs was to inquire into the granting of patent monopolies in Australia over human and microbial genes and non-coding sequences, proteins and their derivatives.

[17] Only at the end of this speech did Heffernan make it clear that the judge he was referring to was Justice Michael Kirby of the High Court of Australia.

[17] Standing Order 193 prohibits senators from making "imputations of improper motives or personal reflections" on currently serving judicial officers.

[18] Heffernan came under prolonged political pressure as a result of this episode, and was eventually asked by Prime Minister John Howard to resign his post as Parliamentary Secretary, which he did.

"[20] On 7 February 2006, The Sydney Morning Herald reported that Heffernan had been forced to apologise to National Party senator Fiona Nash after a public altercation at Canberra Airport the previous day, during which he had told her to "blow it out her backside".

[23][24][25] The president of the NSW Liberal Party, fellow New South Wales Senator Arthur Sinodinos, dismissed the allegations.

[28] In October 2006, Heffernan called for "someone's arse to get kicked" because of delays to the construction of the final major link in the dual carriageway between Sydney and Melbourne.

According to Heffernan, a "colony of whatever they are that live in the edge of the bank of the creek" (platypus) was causing the delay and it was a problem that could be fixed "in ten minutes".

"[30] In the same Bulletin interview, Heffernan caused widespread outrage by suggesting the unmarried and childless Deputy Leader of the Opposition Julia Gillard was unfit for leadership because she was "deliberately barren".

[32] The Bulletin published an interview which quoted Heffernan as stating that Australia had to "settle the north" because millions of people in Asia may find it a "very attractive proposition" if climate change leaves them water-poor.

[37] According to The Age newspaper, in 2007 Heffernan posed as an ASIO agent in a telephone call to John Grabbe, a farm manager in New South Wales.

[40] In response, the Australian Federal Police Commissioner Tony Negus admitted passholders bringing in unauthorised objects "is a risk", but that the AFP regularly consults with parliamentary officials about appropriate security measures.