Greg Sorbara

On November 14, 1991, Sorbara announced that he was joining the race to replace Peterson as leader of the party.[12] He stated, "We have to stop this province's slide into a low-wage, no-growth economy," and spoke of infrastructure investment.[13] During the convention which was held in Hamilton, Ontario on February 9, he finished third on the first ballot, and remained in this position until dropping from the race after the fourth ballot. Sorbara subsequently refused to support either Murray Elston or Lyn McLeod (the eventual winner) on the fifth and final ballot.[14] and did not seek re-election in 1995.[15]

Sorbara supported Dalton McGuinty's successful bid for the provincial party leadership at the 1996 leadership convention. He did not run in the 1999 provincial election, but was elected Party President over Alvin Curling in November 1999.[16] He later won a 2001 by-election in the redistributed Greater Toronto Area riding of Vaughan—King—Aurora, defeating Progressive Conservative candidate Joyce Frustaglio by almost 10,000 votes.[17] Sorbara delivered a statement in May 2010, supporting the minority Muslim sect, Ahmadiyya, who were recently attacked in Lahore for practicing their faith.[18]

The Liberals won the 2003 election, and Sorbara was appointed Minister of Finance in the Ontario Cabinet on October 23, 2003.[19]

Sorbara became involved in a conflict-of-interest controversy not long after his appointment. In late 2003, the Ontario Securities Commission informed Sorbara's office that Royal Group Technologies would be announcing they were under investigation by the OSC. As a former director of Royal Group, this placed Sorbara in a conflict of interest as he also oversaw the OSC. Sorbara could not consult the Premier concerning the conflict of interest as he was restricted by the province's Securities Act from informing anyone else of the impending announcement by the company. Royal Group did not announce the investigation for almost two months.

There were calls for Sorbara to resign after the controversy became public knowledge, but he was cleared of any wrongdoing by the provincial integrity commissioner in August 2004.

On May 18, 2004, Sorbara released the McGuinty government's first budget. The centrepiece was a controversial new Health Premium of $300 to $900, staggered according to income. This violated a key Liberal campaign pledge not to raise taxes, and gave the government an early reputation for breaking promises. The Liberals defended the premium by pointing to the previous government's hidden deficit, and McGuinty claimed he needed to break his campaign pledge on taxation to fulfill his promises on other fronts. This broken promise has created a lasting public relations difficulty for the Liberal Party.

The Ontario Health Premium also became a major issue in the early days of the 2004 federal election, called a week after the Ontario budget. Most believe that the controversy hampered Liberal Prime Minister Paul Martin's bid for re-election.

Also controversial was the elimination of coverage for health services not covered by the Canada Health Act including eye examinations and physical therapy. Other elements of the McGuinty government's first budget were a four-year plan to tackle the deficit left behind by the Conservatives, free immunization for children, investments in education and investments to lower waiting times for cancer care, cardiac care, joint replacement and MRI and CT scans.

On May 11, 2005, Sorbara delivered his second budget. The flagship of the budget was the "Reaching Higher" plan. Investing $6.2 billion over four years, the plan increased accessibility for low-income students with loans and grants while funding more enrollments, expanded medical school spaces, and invested in new faculty, graduate scholarships and research.

The budget also projected breaking a vow to balance the future 2007–08 budget. Sorbara instead aimed at balance in 2008–09.

Sorbara also moved to expand infrastructure spending by encouraging Ontario's large pension plans to invest in the construction of new roads, schools and hospitals. Specific projects in the budget included a 10-year expansion of the TTC and Go Transit, 15,000 new affordable housing units and improved border crossings. NDP leader Howard Hampton described this move as "privatization by stealth."

After a cabinet shuffle on June 29, 2005, Sorbara was also named as the Chair of the Management Board of Cabinet.

Sorbara was re-elected to the Legislature in the 2007 election, and subsequently on October 26, 2007, he announced that he no longer wanted to sit in Cabinet, citing he wanted to devote more time for his constituents and his family.[20]