(written from a Production point of view)
Liska made his film debut in the 1973 George A. Romero horror movie classic The Crazies, in which he and fellow Star Trek movie actor Roger Aaron Brown played soldiers. This was followed with an appearance in the 1981 film Gangster Wars, starring Michael Nouri, Jonathan Banks, Vincent Schiavelli, and Kenneth Tigar. Liska also appeared in 1987's Beverly Hills Cop II along with Ronny Cox, Tommy "Tiny" Lister, Jr., and Dean Stockwell.
Liska also made guest appearances on numerous television series, including Hill Street Blues (with Barbara Babcock and Star Trek III co-star James B. Sikking), Cagney & Lacey (starring Meg Foster), T.J. Hooker (starring Captain Kirk actor William Shatner as well as James Darren and Richard Herd), Hardcastle and McCormick (starring Brian Keith and Daniel Hugh Kelly in the title roles), and The A-Team (with Dwight Schultz, Lance LeGault, William Lucking, and Richard Lynch). In 1982, he and Henry Gibson appeared in an episode of Simon & Simon, and in 1986, he and Jeff Allin co-starred in an episode of St. Elswhere – a series which at the time also starred Chad Allen, Ed Begley, Jr., Norman Lloyd, Deborah May, France Nuyen, Jennifer Savidge, Alfre Woodard, and Jane Wyatt. In 1983, Liska had a small recurring role in the 1982 short lived science fiction TV series Voyagers! as Drake in the episodes "The Trial of Phineas Bogg" (with Harry Townes), and "Jack's Back" (with Michael Ensign, Joie Staton), and Harry Townes). "Voyagers!" also had guest appearances of Jonathan Frakes, William Lucking, Judson Scott, Earl Boen, Ed Begley, Jr., Gregory Itzin, Gregg Henry, Michael Durrell, Norman Snow, Ed McCready, Dan Kern, George Sawaya, John Anderson, Lance LeGault, Ike Eisenmann, David Graf, Fionnula Flanagan, John McLiam, Robert O'Reilly, Tricia O'Neil, Barrie Ingham, Ellen Geer, John Hancock, Bill Erwin, and Paddi Edwards.
In 1993, he and Tim Russ appeared on the series Dark Justice. Five years later, he appeared on JAG with Daphne Ashbrook and Steven Culp. Liska's other TV credits include Knight Rider, MacGyver, Murder, She Wrote (featuring Natalia Nogulich, John Rubinstein, and William Windom), Tales from the Crypt, and J.J. Abrams' Alias. He also appeared in such TV movies as Baby M (1988, with Bruce McGill and Helene Udy), The Bride in Black (1990, with Bob Gunton, David Soul, and Tony Todd), and Calendar Girl, Cop, Killer? (1992, with Ed Lauter, James Sloyan, and Susanna Thompson).
The majority of his later work have been films directed by Richard Donner. These include Maverick (1994, with Henry Darrow, William Marshall, and Bert Remsen), Conspiracy Theory (1997, with Patrick Stewart, Bert Remsen, and Kenneth Tigar), Lethal Weapon 4 (1998, with Jack Kehler, Richard Libertini, and Richard Riehle), and Timeline (2003, with Neal McDonough).