Vacca has been a distinguished lecturer at CUNY Queens College, where he teaches courses in urban studies. Prior to being elected to the City Council in 2005, Vacca served as District Manager of Bronx Community Board 10 for 26 years, and was appointed to the position in 1980, when he was 25 years old, becoming one of the youngest District Managers in the city's history. He had previously served as Chairman of the Board. For numerous consecutive years under his leadership, Board 10 was ranked the cleanest and safest community board in the Bronx.
In early 2005, with Councilwoman Madeline Provenzano term-limited out of office, Vacca announced his candidacy for the 13th Council District seat. Already an established public figure in the East Bronx due to his years as District Manager, he was endorsed by Congressman Joseph Crowley, State Senator Jeffrey Klein, and Assemblyman Michael Benedetto, as well as dozens of community and civic groups, and The New York Times. In the September 13, 2005, Democratic Party primary, he faced four opponents: former Assemblyman Stephen B. Kaufman, Joseph A. McManus, Ismael Betancourt, and Egidio Joseph Sementelli. He won with nearly 40% of the vote; Kaufman captured roughly 25%. In the general election, he defeated Philip Foglia, candidate of the Republican, Conservative and Independence Party lines, with 64% of the vote. In 2009, Vacca ran for re-election under the Democratic and Republican lines, after being cross-endorsed by the Bronx Republican Party. Facing a little-known challenger running on the Conservative Party line, Vacca was easily re-elected to a second term, winning 92.8% of the vote. He easily won election to a final term in 2013 with over 83% of the vote. On Council, Vacca has been a strong advocate for responsible zoning laws and for prevention of overdevelopment. In 2007, Vacca was also named co-chair of the Council's Working Group on School Governance and Mayoral Control, established to guide the Council recommendations upon the expiration of mayoral control in 2009. After months of informal meetings with educators, union leaders, Administration officials, advocates, and parents, the Working Group issued its report in June 2009. The report suggested a new system of municipal control. Later that month, the New York State legislature passed 8903-A, a bill relating to the management and operation of the New York City School District. Vacca has also been influential in protecting funding for the Fire Department of New York. He also has been a proponent of congestion pricing. In August 2017, as chair of the Committee on Technology, Vacca introduced an algorithmic transparency bill, Int. 1696-2017, that would require city agencies "that use algorithms or other automated processing methods that target services, impose penalties, or police persons to publish the source code used for such processing" -- a nationwide first. The bill was influenced by the scholarship of Danah boyd, Kate Crawford, and Cathy O'Neil. After public hearings and negotiation with city agencies, an amended bill, Int. 1696-A, passed the City Council unanimously in December 2017. The amended bill creates a task force to consider the issue and report to the city in late 2019. Researcher Julia Powles, assessing the amended bill in The New Yorker, predicted that the task force's findings will have significant international and domestic impact, but warned that the bill's lack of reporting requirements for city agencies means the task force will need to rely on agencies' voluntary disclosures, which may be sparse.
