Gov. Tom Corbett's decision Wednesday means that same-sex marriage will remain legal in Pennsylvania, without the threat that a higher court will reinstate the ban.
On Tuesday, U.S. District Court Judge John Jones III struck down Pennsylvania's 1996 law banning recognition of gay marriage, calling it unconstitutional.
Corbett's decision goes against his political beliefs. He opposes same-sex marriage and supported thus-far unsuccessful efforts to amend the state constitution to ban gay marriage.
But he says an appeal would be "extremely unlikely to succeed."
Pennsylvania is the 19th state to recognize same-sex marriages. Hundreds of gay couples apply for marriagelicenses after Jones' ruling Tuesday.
Pennsylvania is the last northeastern U.S. state to legalize gay marriage.
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