The youngest of seven children born to immigrants from Ireland, Diegnan was born and raised in South Plainfield, attending Sacred Heart Grammar School and then graduating from South Plainfield High School in 1966.[1][2] Residents of South Plainfield, Diegnan and his wife Anita have been married since 1976 and have two children, Heather and Tara, along with a grandchild.[3][4][5] Diegnan received a B.A. from Seton Hall University in Political Science / Government in 1970 and was awarded a J.D. from the Seton Hall University School of Law in 1973.[3][5] Currently, Diegnan is an attorney in private practice in South Plainfield and is a member of the New Jersey and Middlesex County Bar Associations since 1974. He is also a former instructor of law and accounting at Middlesex County College.[3] Diegnan is currently the borough attorney for Spotswood and formerly served as borough attorney for South Plainfield and Milltown.[5][6][7][8]
Diegnan was first elected to represent the 18th District in 2001 replacing Barbara Buono who had been elected to the New Jersey Senate. He was re-elected to seven more two-year terms. Diegnan served in the Assembly as Deputy Speaker (2008-2016) and Parliamentarian (2005-2016), and was Chairman of the Education Committee and a member of the Regulated Professions and Consumer Affairs Committees.[9]
Diegnan was selected by local Democratic committee members to receive appointment to the 18th District's Senate seat on May 5, 2016, after previous seat holder Peter J. Barnes III was appointed to a judgeship on the New Jersey Superior Court.[10] Sworn into office on May 9, Diegnan won election to the remainder of the term in November, defeating retired judge and former Middlesex CountyFreeholder Roger W. Daley.[11][12]
Diegnan was the primary sponsor of Assembly Bill 3331, introduced in 2003, which creates the certification of Technology Education for teachers.[16] In 2011, he was the primary sponsor of Assembly Bill 3852, which requires voter approval at the annual school election or by the board of school estimate before a new charter school can be authorized to operate in a district.[17] Under the existing system, the Commissioner of the New Jersey Department of Education can grant charters regardless of community opinion, with Diegnan noting that allowing voters and local boards of education a say in the granting of new schools would "help ensure that the charter schools that are created fit the needs of the community". The bill passed in the Assembly in June 2011 by a 47-17 margin.[18]
^"Meet the Leaders - Assemblyman Patrick J. Diegnan, Jr.", TAP into South Plainfield, August 9, 2014. Accessed November 19, 2017. "I was born and raised in South Plainfield. My mother and father were immigrants from Ireland and raised seven children (I am the youngest). I graduated from Sacred Heart Grammar School and South Plainfield High School."
^Smith, Jessica (January 10, 2008). "New-look Boro Council vows to bring integrity". The Sentinel. Archived from the original on September 20, 2015. Retrieved September 5, 2015. He replaces state Assemblyman Patrick Diegnan (D-18), who served as borough attorney for several years.
^Calefati, Jessica. "New N.J. bills could halt growth of charter schools in suburbs, expand in unwelcome areas", The Star-Ledger, June 29, 2011. Accessed July 11, 2011. "One bill (A3852), sponsored by Education Committee Chairman Patrick Diegnan (D-Middlesex), would require voter approval before charters could open in unwelcoming communities. It was approved, 47-17, with 14 abstentions.... 'Community support is crucial in strengthening the establishment of charter schools,' Diegnan said. 'Local input will help ensure that the charter schools that are created fit the needs of the community, thereby strengthening the entire public education system.' Taxpayers currently have no say over where charter schools are located and opposition to their growth in high performing suburban districts has been mounting in recent months because the state Department of Education is reviewing applications to open new charters."