McGuckin earned a bachelor's degree in history from Providence College in 1983 and a law degree from Seton Hall University Law School in 1987. He is a municipal attorney in private practice with more than 28 years serving municipalities as a solicitor, prosecutor and attorney for planning and zoning boards. He was appointed by the state Supreme Court to serve on the district ethics committee for Ocean County and is a board of trustees member for the N.J. Institute of Local Government Attorneys.

Previously, McGuckin was a Toms River councilman from 2004 to 2011, serving as president each year.

A father of three daughters, he and his wife reside in Toms River.