Williams entered federal parliament at the
2013 election where he won the seat of
Hindmarsh with a 1.89 percent margin from a 7.97 percent
two-party-preferred swing, defeating
Australian Labor Party incumbent
Steve Georganas. The only South Australian seat to change hands in 2013, Hindmarsh became the most marginal seat in South Australia and the only marginal seat of the incoming federal government in South Australia. During the 2013 election campaign Williams committed to opposing any changes to the existing evening aircraft flight curfew at
Adelaide Airport, centrally located in the Hindmarsh electorate. However, in December 2013 the
Abbott government changed the curfew to allow Cathay Pacific international passenger flights to land outside the established curfew times. In 2015 it was reported that Liberal insiders were considering Williams to be the preselected Liberal candidate for the state seat of
Morphett if he failed to retain
Hindmarsh at the
2016 federal election. When the preselection contest took place in April 2017, there was a dead-heat between Williams and
Stephen Patterson, followed by a random ballot won by Patterson, who went on to successfully challenge the incumbent Liberal member,
Duncan McFetridge. ==References==