Activists had protested the line in the upcoming comedy "The Dilemma," in which star Vince Vaughn refers to an electric car as "gay."
Howard told the Los Angeles Times Friday the remark was part of the script and spotlights the flaws in Vaughn's character.
"I defend the right for some people to express offense at a joke as strongly as I do the right for that joke to be in a film," Howard said in a written statement to the Times. "But if storytellers, comedians, actors and artists are strong armed into making creative changes, it will endanger comedy as both entertainment and a provoker of thought."
The Hollywood Reporter said Saturday the Gay & Lesbian Alliance Against Defamation has argued that Universal Pictures saw the offensive nature of the line and acknowledged it by cutting it from the trailers for the film.
"The Dilemma" hits theaters Jan. 14.
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