Crooks was born in West Flamboro, Ontario and the son of James Crooks & Jane Cummings. He studied at Upper Canada College and the University of Toronto. During his time in Toronto, he studied law and was called to the bar in 1851. Crooks married Emily Ann C. Evans in 1857. Their child, Lawrence Ogden Crooks, was born in 1858. During the early 1860s, Adam Crooks successfully appealed a lower court decision against the Commercial Bank of Canada before the Judicial Committee of the Privy Council in England. In 1863, he was named Queen's Counsel. Near the end of his life, he suffered from problems with his physical and mental health and was forced to retire from public life. He died in Hartford, Connecticut.
