(written from a Production point of view)
Timoney graduated from Fairfield University in Connecticut. His mother was game show host Mary Gardiner and his brother is actor and voice actor Bill Timoney. He was married to voice actress Simone Grant Timoney until her death in 2005.
Timoney has been a certified USA Hockey ice hockey referee and seminar instructor. He worked as stunt ice skater on the crime movie The January Man (1989, with Bill Cobbs and Jerry Rector) and the sports drama By the Sword (1991, with F. Murray Abraham, Christopher Rydell, Brett Cullen, and Doug Wert) and also appeared as the ice hockey coach in a 2016 Dunkin' Donuts commercial. 
Prior to his appearance in Star Trek, Timoney played an Army major in the television drama The Dollmaker (1984). Further acting work includes episodes of A Bit of a Do (1989), All My Children, Great Performances (1993, with Victor Garber), Live from Lincoln Center (2000 and 2001), Ed (2003, with William Sadler and Ted Sutton), and The Knights of Prosperity (2007, with Kevin Michael Richardson), voice work in the animated series Rôdosu-tô senki (1991) and Gokudô-kun man'yûki (1999), and featured parts in the television drama Love and Betrayal: The Mia Farrow Story (1995), the drama Last Chance (1999, with Charles Dennis), the horror film Solomon's Requiem (2004), and the television comedy Special Unit (2006, with David Figlioli).
Besides acting, Timoney worked as stand-in for Bruce Willis on the thriller Mortal Thoughts (1991) and on the action sequel Die Hard with a Vengeance (1995, with James Saito, John Doman, and Tony Brubaker) and more recently for Bryan Cranston on the drama The Upside (2017) and the war drama Last Flag Flying (2017). He also performed voice work as part of the ADR Loop Group for the thriller The Successor (1996), the crime drama The Devil's Own (1997, with George Hearn and Mitchell Ryan), and the comedy Snatched (2011, with Kate Vernon).
More recent acting credits include episodes of Mildred Pierce (2011, with Mark Margolis and Margaret Reed), The Michael J. Fox Show (2014), and He's With Me (2013-2015), the short thriller The Grid (2013), and the television crime drama Root For The Villain (2017). He has also been working for theater, most recently with a leading and producing role in the play "The Bardy Bunch" at The Mercury Theater in Chicago.