(written from a Production point of view)
Michael Tierney (born 24 January 1965; age 55) is the actor who played Glinn Tajor in the Star Trek: The Next Generation sixth season episodes "Chain of Command, Part I" and "Chain of Command, Part II". He received no credit for his appearances. Tierney also played several background Cardassians on Star Trek: Deep Space Nine.
Beside his appearances in Star Trek, Tierney was featured in the comedy Religion, Inc. (1989), the Freddy's Nightmares episode "Interior Loft Later" (1990, with Craig Richard Nelson and Margot Rose), the drama Eddie Presley (1992, with Daniel Roebuck, Lawrence Tierney, Buddy Daniels, and Shelly Desai), and the science fiction film The Warlord: Battle for the Galaxy (1998, with Carolyn McCormick, John Pyper-Ferguson, Marjorie Monaghan, Joel Swetow, Lilyan Chauvin, Dick Miller, and Steven E. Daniels).
In 2000, Tierney worked as writer, director, actor and producer on his debut Evicted. The film features his uncle Lawrence Tierney and his cousin Terence Tierney and opened the 1st Annual Melbourne Underground Film Festival in Melbourne Australia in July of 2000. Following a supporting role in the 2002 drama White Boy, Tierney started a career as Joe Blow in the adult film industry. Between 2005 and 2010 he worked on over 150 video productions and received two Adult Video News Award nominations in 2007 and 2011.
Tierney left the adult film business in 2010 and produced and starred in the documentary The Last Days of Joe Blow in 2013.  He is also writing the nonfiction novel "Hardcore" about these years.
More recently, Tierney was cast in the thriller The Second Coming, released in 2015.