John Howard served as Prime Minister from 1996 until 2007, the second-longest prime ministerial term after Robert Menzies. One of the first programs instigated by the Howard Government was a nationwide gun control scheme, following a mass shooting at Port Arthur. The government sought to reduce Australia's government deficit and introduced industrial relations reforms, particularly as regards efficiency on the waterfront. After the 1996 election, Howard and treasurer Peter Costello proposed a goods and services tax (GST) which they successfully took to the electorate in 1998. In 1999, Australia led a United Nations force into East Timor to help establish democracy and independence for that nation, following political violence.