DiPietro was born in Buffalo, New York. His parents moved the family to the Village of East Aurora where he subsequently attended Immaculate Conception Elementary and East Aurora High School. He earned a degree in Business Administration from Wittenberg University in 1985. DiPietro began his career at M&T Bank in Buffalo but left after a few years to work as a consultant to small businesses. In 1991 he assumed control of his parents' dry cleaning business in Amherst, New York.
Political career
He was elected a trustee of the Village of East Aurora in 1999 and mayor in 2002. After serving as mayor for six years, he set his sights on higher office, running in the Republican primary for the 59th New York State Senate District against incumbent Dale Volker in 2008 and challenger Patrick Gallivan in 2010. He ran unsuccessfully as the Tea Party candidate in the 2010 general election for the senate seat. In 2012, he won a seat in the New York State Assembly. In 2013, he introduced legislation to repeal the NY SAFE Act. Assemblyman David DiPietro has demonstrated a conservative stance. He voted against proposed medical marijuana legislation, the Compassionate Care Act, and motions dated June 3, 2013 and May 27, 2014. DiPietro was one of 13 nay votes when the bill passed on June 20, 2014. He voted against emergency access to medical marijuana on June 9, 2015; the bill passed, 130-18. However, DiPietro voted for adding opioid-use disorder to the list of conditions treatable by medical marijuana on June 6, 2018. In 2019 Assemblyman DiPietro became the Assembly sponsor of Bill# A05498 which proposes a constitutional amendment to divide the state into three autonomous regions DiPietro voted against key votes related to policies concerning affirmative action, paid family leave, increasing the minimum wage and prohibiting workplace discrimination based on reproductive health decisions. He voted against state-funded projects addressing climate change and a three-year prohibition of hydraulic fracturing. DiPietro has been described as a politician who "can be counted on to defend the principles of a free society: Life, Liberty, and Property" through "the wisdom of our Founding Fathers."