The state Senate is poised to vote today on a proposed amendment to the state Constitution that would exclusively define marriage as a union between a man and a woman.

The Senate Appropriations Committee, chaired by Republican state Sen. Gibson Armstrong of Refton, passed the proposed amendment 18-8 Monday after another testy exchange between state Sen. Vince Fumo, who opposes the amendment, and one of its supporters.

The bill's author, state Sen. Mike Brubaker of Warwick Township, said he believes there's widespread support for the amendment from Republicans and Democrats in the Senate.

"It was a very strong vote out of Appropriations," said Brubaker, a Republican. "We got a strong vote out of Judiciary (Committee)" on March 18.

The proposed amendment says Pennsylvania would not recognize any other form of marriage except man-woman unions. The amendment also bans anything resembling the "functional equivalent" of marriage, like a civil union.

While proponents say the amendment is necessary to prevent a potential lawsuit that could legalize civil unions and gay marriage, opponents say the amendment would cramp the rights of non-married people, even heterosexuals, when it comes to adoptions, estate planning, power of attorney issues and health benefits.

"There seems to be an awful lot of unintended consequences in this bill," said state Sen. Sean Logan, an Allegheny County Democrat who voted against it.

Supporters say the amendment's language would not change current law other than to provide constitutional protection for the state's 1996 Defense of Marriage Act, which defines marriage as heterosexual unions.

Proponents do not want to "interfere" with "health insurance benefits or the ability to do wills or power of attorney," said state Sen. John Gordner, a Columbia County Republican.

Fumo, like he did last week during a hearing, directed sharp questions at supporters of the amendment and engaged in a prickly exchange with Gordner.

Fumo said proponents of the bill are aiming to discriminate against homosexuals by preventing civil unions.

"This is not for the sanctity of marriage; this is for discrimination against gays," Fumo said to Gordner.

"This is to preserve marriage," Gordner said.

"To preserve the word marriage," Fumo said.

"It is to preserve marriage, the sanctity of marriage," Gordner said. "There's no doubt from proponents of this there's also the intent not to allow the judiciary, for instance like they did in New Jersey, to allow something else that's the functional equivalent of marriage."

Fumo said, "So this is in essence to discriminate against gays because some judge may say it's OK to have a civil union or whatever you want to call it. This is what this is designed for, right?"

Gordner said, "I would not argue that that would be the effect."

Gordner's answer prompted Fumo to call the amendment "morally wrong." "It is unpatriotic; and it is disgraceful," he said.

In order to become law, a proposed amendment has to pass the Senate and House twice, one time for each chamber in consecutive two-year legislative sessions. The amendment is then put to a statewide voter referendum.

E-mail: dpidgeon@lnpnews.com