Silver was born on July 2, 1946 in Manhattan, New York, the son of May (née Zimelman), a substitute Teacher, and Irving Roy Silver, a clothing sales executive. Silver was raised Jewish on the Lower East Side of Manhattan and attended Stuyvesant High School.
Silver got his big acting break starring in El Grande de Coca-Cola in 1974. Producers Richard Flanzer and Roy Silver (no relation) opened it at the famed Whisky a Go Go on the Sunset Strip in Los Angeles. The production ran for more than a year. Silver and his co-star, actor Jeff Goldblum, were discovered by Hollywood film agents during this show's run.
In 1975, he married a social worker, later Self magazine Editor, Lynne Miller; the marriage lasted until 1997, when they divorced.
In 1976, he made his film debut in Tunnel Vision, and also played a placekicker in the football comedy film Semi-Tough. From 1976 to 1978, he had a recurring role as Gary Levy in the sitcom Rhoda, a spin-off from The Mary Tyler Moore Show. Additional screen roles include a Psychiatrist in the horror story The Entity (1983), the devoted son of Anne Bancroft in Garbo Talks (1984), an incompetent detective in Eat and Run (1986), the pistol-wielding psychopath stalking Jamie Lee Curtis in 1989's Blue Steel, and the lead in Paul Mazursky's Oscar-nominated Enemies: A Love Story (1989).
He starred as Jerry Lewis's character's son in the multi-episode "Garment District Arc" of the television crime series Wiseguy (1988).
In 1989, he co-founded the Creative Coalition, an entertainment industry political advocacy organization that champions for First Amendment rights, public education, and support for the arts.
He portrayed two well-known attorneys in films based on actual events, playing defense attorney Alan Dershowitz in the drama Reversal of Fortune (1990), based on the trial of Claus von Bülow. and defense attorney Robert Shapiro in the television film American Tragedy (2000), the story of the O. J. Simpson trial.
From 1991 to 2000, Silver served as President of the Actors' Equity Association. He played a film Producer in Best Friends opposite Burt Reynolds and Goldie Hawn (1982), an actor in Lovesick (1983) and a film Director in Mr. Saturday Night (1992). Silver portrayed a corrupt, rogue senator in the 1994 Jean-Claude Van Damme sci-fi thriller Timecop.
On television in 1998, he starred opposite Kirstie Alley for season two of her TV comedy series Veronica's Closet.
Silver was a member of the Council on Foreign Relations. In 2000, he co-founded the organization One Jerusalem to oppose the Oslo Peace Agreement and to maintain "a united Jerusalem as the undivided capital of Israel".
From 2001–02 and again from 2005–06, he had a recurring role as presidential campaign adviser Bruno Gianelli on the NBC series The West Wing.
Silver, who had been a lifelong Democrat, left the party and became an independent and a supporter of President George W. Bush after the September 11 attacks, citing those attacks and Democratic policies regarding terrorism as reasons. He spoke at the 2004 Republican National Convention, continued to support President Bush, and was appointed Chairman for the Millennium Committee by New York Mayor Rudy Giuliani.
One of his final film performances was as a judge in another true story, 2006's Find Me Guilty, directed by Sidney Lumet and starring Vin Diesel.
In one of his last televised interviews, he told Sky News that Senator John McCain's choice of Sarah Palin as his running mate in the 2008 Presidential election was a "brilliant political choice" but that a part of him wished to "see an African American become President in my lifetime". According to the obituary printed by The New York Times, his brother, Mitchell Silver, noted that "He told me that he did vote for Barack Obama in the end".
Silver, a long-time smoker, died on March 15, 2009, of esophageal cancer, which had been diagnosed two years earlier. He was 62 years old. Silver is survived by both parents, brothers Mitchell and Keith, son Adam, and daughter Alexandra. His remains were interred at Westchester Hills Cemetery in Hastings-on-Hudson, New York.