Hawley started his career in 1966 as a 17-year-old boy, hot walking horses at a Toronto racetrack. Two years later, he became a regular rider at racetracks in Ontario. He learned how to ride under the tutelage of Duke Campbell, a trainer Sandy still credits today as one of his greatest sporting influences.
Hawley won his first career race aboard Fly Alone on October 14, 1968 at Woodbine, going on to win three more races in a modest first year. Hawley went on to become North America's top apprentice jockey in 1969 and then led in victories for the years 1970, 1972, 1973 and 1976. In 1970 he was the continent's leading race-winning jockey with 452 wins. In 1972 he tallied another North American title with 367 wins, and in the 1973 season, he became the first jockey to ever win 500 races in one year breaking Bill Shoemaker's record. He closed the 1973 season with 515 wins.
Hawley won the Lou Marsh Trophy in 1973 and 1976 as Canada’s top athlete and was decorated with the Order of Canada, the country’s highest individual civilian honour for outstanding accomplishments by a citizen. In addition to winning a large number of major Stakes races in the United States, four times he won Canada’s most prestigious thoroughbred horse race, the Queen's Plate. He also holds the mark for most wins among jockeys in the Canadian Oaks with eight. Twice, Hawley won seven races in a single day at Toronto’s Woodbine Racetrack and at Santa Anita Park had six wins in a single day on two occasions. Hawley scored his 5,000th career win aboard Mighty Massa on June 27, 1986 at Canterbury Downs, and he is the youngest in the history of the sport to reach that plateau. He won his 6,000th race aboard Summer Commander on November 26, 1992 at Greenwood. In 1986 he was awarded Woodbine's Avelino Gomez honour. He returned to Woodbine in 1988.
Sandy Hawley’s most significant race has been not on the back of a thoroughbred but against virulent skin cancer. Diagnosed with skin cancer in 1987, doctors only gave him a few months to live but he fought to overcome the disease with experimental drugs, a careful high-fiber diet, and his sheer determination. Hawley now has a clean bill of health, but receives a series of vaccine shots once a year in California.
Overall, his career as a jockey spanned 31 years from 1968 to his retirement on July 1, 1998. Hawley had 31,455 mounts, garnering 6,449 wins and captured 18 Woodbine riding titles, 13 Fort Erie meets, nine Greenwood championships, nine Ontario titles, and eight Canadian honours. His final ride was on Terremoto in the Grade III Dominion Day Stakes at Woodbine.
After his retirement from racing Hawley began a new career as a public relations ambassador for the Ontario Jockey Club.
Hawley currently resides in Pickering, Ontario with his wife, Lisa, and sons, Bradley and Russell.