Associated Press - April 15, 2009 2:25 PM ET

CONCORD, N.H. (AP) - At least 500 people crowded into New Hampshire's Statehouse in an emotional and sometimes boisterous hearing over whether allowing gay marriage would weaken or strengthen the family institution.

Supporters argued gay marriage is a civil rights issue and excluding gays would be discriminatory.

Opponents countered that marriage is a sacred religious institution that would be cheapened by allowing gays to marry. They also said gay marriage defies nature and could harm children.

Many attending Wednesday's hearing also participated in dueling demonstrations before the hearing.

Currently, Connecticut, Massachusetts, Vermont and Iowa allow gay couples to marry. California briefly allowed gay marriage last year, but a voter initiative in November repealed it.

The Rt. Rev. V. Gene Robinson, the U.S. Episcopal Church's first openly gay bishop, urged the Senate Judiciary Committee not to base its recommendation to the full Senate on fear of losing the next election. He said he's praying they will find courage to rise above their political considerations, adding that if full marriage equality will be right some day, it is right today.

Roman Catholic Bishop John McCormack submitted a letter arguing that same-sex marriage would be inconsistent with thousands of years of human civilization.

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