In 2006, former federal opposition leader
Kim Beazley approached Tinley to run for the federal
Division of Stirling as the
Labor Party's endorsed candidate at the
2007 election. The sitting member,
Liberal MP
Michael Keenan, retained the seat with a slightly reduced majority. Upon the resignation of former
premier Alan Carpenter from the safe Labor state seat of
Willagee, Tinley was preselected to run for Labor at the
resulting by-election on 28 November 2009. He was ultimately elected as the member for Willagee with over 60% of the two-party-preferred vote against the
Greens' Hsien Harper. Upon Labor's election to government at the
2017 state election, Tinley was appointed to the
McGowan Ministry as minister for mines and petroleum, Veterans Issues, and Youth on 17 March. Five days later on 22 March, Tinley resigned as Mines and Petroleum minister, to avoid any claim of conflict of interest due to a family member working in the industry, and exchanged the Housing portfolio with
Bill Johnston. Tinley later became Western Australia's Asian Engagement Minister. On 19 March 2021, after the
2021 state election, Tinley was unexpectedly removed from cabinet. After spending almost three years as a backbencher, on 14 March 2024 Tinley announced that he would not seek re-election at the
2025 state election. ==Returned & Services League of Australia==