The leader of Rhode Island’s Roman Catholic Diocese says state Governor Lincoln Chafee is wrong to threaten to veto legislation that would put equal marriage to a popular vote.

Bishop Thomas Tobin, who opposes equal marriage and has described it as a sin, released a statement on Friday calling Governor Chafee’s veto threat “undemocratic.”

The bishop said it should be up to citizens to decide whether Rhode Island joins the rest of New England in allowing gay couples to marry.

Governor Chafee, an independent, who supports equal marriage, said on Thursday he’s inclined to veto legislation that would place marriage equality on the ballot as a referendum and instead wants lawmakers to pass it themselves.

Opponents have suggested putting the question before voters, but supporters say the issue is one of civil rights and should not be decided by a referendum.