David Peterson was the twentieth Premier of Ontario from June 26, 1985 to October 1, 1990, and the first Liberal premier of Ontario in 42 years. He was born in Toronto, Ontario in 1943, and earned degrees from the University of Western Ontario (B.A.) and the University of Toronto (Ll.B.). Peterson was called to the bar in 1969.

The Hon. David Peterson
Rank:20th
Term of Office:June 26, 1985 - October 1, 1990
Predecessor:Frank Miller
Successor:Bob Rae
Date of Birth:1943
Place of Birth:Toronto, Ontario
Spouse:Shelley Peterson
Profession:Businessman
Political Party:Liberal

David Peterson was first elected as a Liberal MPP from London in 1975. He became Liberal leader and Leader of the Opposition in 1982.

In 1985, he began the Ontario election campaign with several problems. Dismal polling numbers, a Canada-wide trend against electing Liberal politicians, and a 42 year history of futility by the Ontario Liberal Party all led to predictions that his party was on the verge of annihilation. Instead, he came within 4 seats of defeating the Frank Miller's Progressive Conservative government, resulting in an unstable minority government. NDP Leader Bob Rae proposed a coalition government with the Progressive Conservatives to allow for a majority government, something Frank Miller rejected. Bob Rae quickly offered the coalition to the Liberals, which David Peterson accepted. On June 26, 1985, David Peterson was sworn in as Premier of Ontario in a coalition government between the Liberals and NDP. After the expiration of the coalition agreement in 1987, David Peterson would successfully win a majority, eliminating the NDP from government.

Peterson's government eliminated extra billing by doctors, and Peterson was a vocal opponent of free trade with the United States. Peterson was one of the architects of the "Meech Lake" constitutional accord, which never became part of the Canadian constitution, and which proved dangerously divisive. In 1987, Peterson's Liberals won a landslide majority government, taking three quarters of the seats in the legislature.

The Peterson years saw some of Ontario's best economic times. Fiscally, their record was mixed. In 1989-1990, when deficit spending was de rigeur in most western governments, the Liberal government registered a slight surplus. However, in their next budget, they predicted a surplus, and Ontario turned out to have a deficit of over three billion dollars.

When Peterson called an election in 1990, he was still popular, owning a 54 per cent approval rating, and standing at 50 per cent in the polls. However, his luck turned immediately upon calling the election. Disappointed by high expectations, groups representing several interests, such as teachers, doctors, and environmentalists, came out against Peterson on television, radio, in print, and at Liberal campaign events. The general public felt that Peterson's early election call was cynical, and the party also appeared to be desperate when half-way through their campaign they proposed to cut the provincial sales tax. Some believed that Peterson was a better premier when his government was in a minority position. Many Ontarians, independently of one another, decided to vote strategically and reduce the Liberals to a minority government. This, combined with a well run NDP campaign and a strong performance by NDP leader Bob Rae, ended Peterson's tenure as premier. On September 5, 1990, the NDP out-polled the Liberals 38% to 34%, and Bob Rae's New Democrats were able to win a majority government. David Peterson even lost his own seat. Peterson resigned as premier on October 1, 1990.

Peterson's greatest legacy, it could be argued, is that he turned around Liberal fortunes in Canada. Prior to the 1985 Ontario election, the future of the Liberal Party looked bleak. They governed in no province, and, federally, were down to 40 seats. In some provinces, the Liberals had been completely wiped from both federal and provincial representation in the legislatures. Slowly, beginning in Ontario with Peterson's surprise government, the party reversed the trend. By October, 2003, the Liberals were in power federally, and in each of the three largest provinces in the country, as well as in Newfoundland. In four provinces, they formed the opposition.

David Peterson was the Founding Chairman of the Toronto Raptors Basketball Club of the NBA, and was a member of Toronto's Olympics Bid Committee. Since leaving politics, he has been a professor at York University in Toronto, a senior partner and chairman of the Toronto law firm Cassels, Brock & Blackwell, and has been director or member of several charitable, cultural, and environmental organizations. He is married to actress Shelley Peterson.

Preceded by:
Frank Miller
List of Ontario premiers Succeeded by:
Bob Rae