Bishops Michael Burbidge of Raleigh and Peter Jugis of Charlotte added their voices to a news conference at the Legislature. The group says North Carolina is the only state south of Washington and east of New Mexico without such an amendment.
Legislative leaders have blocked debate on similar bills in recent years saying the state's laws are adequate. The group said that a ban should be written into the constitution to prevent a court from overturning state law.
"We are sponsoring this legislation because we firmly believe that North Carolina's marriage laws are at risk of being redefined by activist courts to include same-sex couples," said Senator Jim Forrester (R-Gaston).
Parents of gay children attending the news conference told reporters that a gay-marriage ban violates their rights to equal protection.
Other religious groups also voiced opposition.
In a statement emailed to Eyewitness News, Jack McKinney, Pastor of Pullen Memorial Baptist Church and also Co-chair of the North Carolina Religious Coalition for Marriage Equality, said: "We are saddened that some of our legislators continue to use the issue of same-sex marriage to try and re-write our state’s constitution and create a hostile environment for gay, lesbian, bisexual, and transgender citizens in North Carolina."
"Such an amendment would not only deny equal marriage rights, which are already denied to gay North Carolinians, but could also prohibit any recognition of civil unions, domestic partnerships, or similar relationships in the state. The language of the bill is so broad it could prevent private companies from extending domestic partner benefits to their employees," he continued.
