An independent on the Napier City Council, Tolley was encouraged to join the
Labour Party by incumbent
Napier MP
Geoff Braybrooke but declined, instead joining the National Party. She was interested in being a candidate for National at the
1996 general election, but had not been a member of the party for long enough. In 2000, her members bill—the Films, Videos, and Publications Classification (Prohibition of Child Pornography) Amendment Bill—was introduced. The bill responded to, and sought to overturn, the Court of Appeal's decision on
Moonen v Film and Literature Board of Review, which had found that the right to freedom of expression in the
New Zealand Bill of Rights Act 1990 held even in the
Film and Literature Board of Review's consideration of photographs depicting children in sexualised poses. The bill was eventually voted down because the government did not consider
Moonen to sanction child pornography. Issues around censorship were progressed soon after through an inquiry into the
Films, Videos, and Publications Classification Act 1993 and a government amendment passed in 2005. In the
2002 election, she unsuccessfully contested the Napier seat against Braybrooke's successor,
Russell Fairbrother. Along with many other National MPs, Tolley did not escape the collapse of the party's vote that year, and so did not return to Parliament as a list MP. She did return at the
2005 general election, having won the
East Coast electorate over Labour candidate
Moana Mackey, daughter of the previous East Coast MP
Janet Mackey. She held the electorate at the four subsequent elections. When National won the 2008 general election, she became the first woman
Minister of Education. She continued in senior roles in the
Fifth National Government until its defeat in 2017 and thereafter became
Deputy Speaker. In that role, she chaired a cross-party steering group steering group to develop a parliamentary code of conduct, as an outcome of an independent review into bullying and harassment in the parliamentary workplace. This occurred after interrupting Youth MP Lily Dorrance's speech at the
2022 Youth Parliament, leaving Dorrance "humiliated", which Tolley said made her "all the more aware of the issues". At the end of 2019, Tolley declared her intention to run as a list-only candidate in the 2020 general election in hope of being able to be appointed
Speaker of the House if National were able to form a government. She was succeeded as National's candidate for the East Coast electorate by
Rotorua District Councillor
Tania Tapsell. However, in June 2020, with National polling poorly, Tolley announced that she would instead retire at the
2020 election. She gave her valedictory statement on 23 July 2020. == Minister in the Fifth National Government ==