POMONA, N.J. —  The widow of Martin Luther King Jr. called gay marriage a civil rights issue, denouncing a proposed constitutional amendment that would ban it.

Constitutional amendments should be used to expand freedom, not restrict it, Coretta Scott King (search) said Tuesday.

"Gay and lesbian people have families, and their families should have legal protection, whether by marriage or civil union," she said. "A constitutional amendment banning same-sex marriages (search) is a form of gay bashing and it would do nothing at all to protect traditional marriages."

Last month, President Bush said he backed an amendment that would ban same-sex unions, calling marriage "the most fundamental institution of civilization."

On Monday, more than two dozen black pastors rallied against gay marriage at a church in Atlanta, attempting to distance the civil rights struggle from the gay rights movement. They signed a declaration outlining their beliefs that marriage should remain a union between a man and a woman.

"To equate a lifestyle choice to racism demeans the work of the entire civil rights movement," the statement said. "People are free in our nation to pursue relationships as they choose. To redefine marriage, however, to suit the preference of those choosing alternative lifestyles is wrong."

King, the widow of the slain civil rights leader, made her comments Tuesday during a speech at The Richard Stockton College of New Jersey (search).