(written from a Production point of view)
Dan Gauthier (born 2 December 1963; age 55) is the actor who played Ensign Sam Lavelle in the Star Trek: The Next Generation seventh season episode "Lower Decks". His mok'bara outfit from this episode was later sold off on the It's A Wrap! sale and auction on eBay and misspelled his name on the tag as David Gauthier. 
He has had recurring roles on several television series, including Kyle Parks on Sisters (with Ashley Judd), Jonathan Mitchell on the short-lived Courthouse (with Bob Gunton), Dick Harrison on Beverly Hills, 90210, and Jeff Baylor on Melrose Place. He was also a regular during the last season of Tour of Duty, playing Lieutenant John McKay. Star Trek: Deep Space Nine and Star Trek: Voyager guest actor Patrick Kilpatrick also joined the series at this time.
Gauthier went on have a regular role as Detective Matt Liston during the 1995-1996 season of the hit sitcom Ellen. More recently, he was part of the principal cast of the soap opera One Life to Live, on which he plays the role of Kevin Buchanan. He also played this role in multiple episodes of All My Children. In 2007, he received a nomination from the Daytime Emmy Awards for his performance on One Life to Live. At the time Gauthier was on One Life to Live, he co-starred with Renee Goldsberry and Lisa LoCicero.
He appeared in the 1991 television movie N.Y.P.D. Mounted with Voyager star Roxann Dawson and Deep Space Nine guest star Cliff DeYoung. In 2002, he starred in the science fiction movie Groom Lake, written and directed by and co-starring William Shatner. Deep Space Nine and Voyager guest actor Tom Towles also starred in this film.