Thomas L. Leonard III (born April 20, 1981) is an American attorney and politician. He is a former member of the Michigan House of Representatives who served as Speaker of the House from 2017 to 2019. Elected in 2012 to succeed term-limited Paul Opsommer, Leonard represented the residents of Clinton and Gratiot County. Prior to that, he worked as a prosecutor. Leonard unsuccessfully ran for Michigan Attorney General in 2018 and was nominated by President Donald Trump to be the United States Attorney for the Western District of Michigan.