The Indecent Proposal star launched the 2013 event on Thursday (17Jan13), just days after U.S. President Barack Obama announced plans to tighten America's gun laws in the aftermath of the Connecticut school massacre.
Debate has since raged over whether gun violence in movies has an impact on impressionable audiences, and Redford has now spoken out to urge filmmakers to think more carefully about their work.
During a press conference on Thursday, he told reporters, ""I'm thinking back (to) when we started Sundance, back in 1980, and I remember, (U.S. President Ronald) Reagan was shot at that same year. I remember there was talk about gun control coming up then. Now it's 30 years later. I think it's absolutely not only appropriate but overdue to have a dialogue...
""When I was driving along the street the other day in L.A., I saw two (movie poster) billboards where guns were featured prominently... with a pleasant, happy-looking young couple... My thought was: 'Does my industry think guns will help sell (movie) tickets?'... It seems like a question worth asking my own industry. And maybe there's a reason, maybe yes (is the answer to the question).""
Gunman Adam Lanza shot dead 20 kids and six staff members at Sandy Hook Elementary School in Newtown on 14 December (12). Lanza, 20, is also believed to have killed his own mother before turning the gun on himself.
The Sundance Film Festival runs until 27 January (13).