MONTPELIER, Vt. --On March 27, 2003, U.S. Rep. Bernard Sanders voted against a bill that would have set up a national coordinator for the Amber Alert system, which warns the public when a child has been kidnapped.

It's a vote that has come back to haunt him, and one that demonstrates the political liability that can come from even the most well-intentioned "nay" or "yea."

The vote has become a central issue in the heated campaign between Sanders, an independent, and Republican Richard Tarrant, in the race to succeed retiring U.S. Sen. James Jeffords.

Again and again, in TV and radio commercials, Tarrant has hammered away at Sanders over the vote, forcing the veteran congressman to air ads of his own defending his voting record.

"The Amber Alert is a great idea," the speaker in one ad says. "It alerts the public when a child has been kidnapped. Bernie Sanders voted against it. ... Bernie should know better."

The motivation behind the campaign was simple, said Tarrant campaign manager Tim Lennon.

"I think U.S. Rep. Sanders is wrong. Four-hundred members of Congress and a unanimous vote in the Senate say he was on the wrong side of that issue," said Lennon.

Sanders was one of only 14 House members to vote against the bill, which passed the Senate 98-0, with U.S. Sen. Patrick Leahy, D-Vt. -- a Sanders supporter -- voting in favor.

The same day, Leahy issued a 33-page statement denouncing the Republican-led House for tacking provisions onto the bill that he feared would be ruled unconstitutional.

"After months and months of trying, we've finally gotten a green light for a national Amber Alert program," Leahy said in his April 10, 2003, statement. "The problem has never been winning enough support to pass it. The problem has been that our bill has garnered such strong support that it has been abused as a sweetener for highly controversial add-ons."

Among the add-ons placed on the bill by House Republicans was one restricting the discretion of federal judges in crafting sentences for a range of crimes.

Sanders campaign manager Jeff Weaver said Sanders is a strong supporter of the Amber Alert program, and signed onto a 2004 letter to the House leadership requesting full funding for it.

But Sanders voted against the Amber Alert bill because he felt its sentencing provisions were an unconstitutional intrusion by Congress, taking power that should rest with the judiciary.

The late Supreme Court Chief Justice William Rehnquist agreed. He wrote a letter to the Congress saying the sentencing provisions would do "serious harm to the basic structure of the sentencing guideline system" used by federal judges "and would seriously impair the ability of courts to impose just and reasonable sentences."

Lennon said Sanders "wants to have it both ways" on restricting sentences. He noted that Sanders says on his Web site that he supports mandatory minimum sentences for repeat sex offenders.

Sanders' camp said there is no inconsistency. Congress often passes mandatory minimum sentences for various crimes, but Sanders believed the sentencing provisions in the Amber Alert bill restricted sentencing in a much broader way, Weaver said.

Linda Fowler, a Dartmouth College professor of government, said Republicans in Washington are adept at designing legislation with the goal of embarrassing Democrats.

Being in the majority in both the House and Senate, "they can use their control in bringing things to the floor to again create highly symbolic votes," Fowler said.

She points to a case in 2002 in which Democrats, faced with a bill that set up a new Transportation Security Administration whose employees wouldn't have union protection, would "either be voting against unions or voting against homeland security."

U.S. Sen. Max Cleland, D-Ga., sided with labor in that vote, and was defeated for re-election after his opponent ran commercials saying Cleland -- who served in Vietnam -- was weak on national security.

"Every voter says they hate negative advertising," Fowler said. "But the fact of the matter is every campaign consultant knows that it works -- unless the charges can be shown to be patently untrue and unfair."

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