Two Republican senators on either side of the abortion debate on Thursday called for NARAL Pro-Choice America to withdraw its television ad accusing Supreme Court nominee John Roberts (search) of siding with violent abortion protesters.
The ad, which began airing this week, says: "Supreme Court nominee John Roberts filed court briefs supporting violent fringe groups and a convicted clinic bomber."
Senate Judiciary Committee Chairman Arlen Specter, R-Pa., sent a letter to NARAL calling the ad "blatantly untrue and unfair."
"The NARAL advertisement is not helpful to the pro-choice cause, which I support. When NARAL puts on such an advertisement, in my opinion it undercuts its credibility and injures the pro-choice cause," Specter wrote.
Sen. Orrin Hatch, R-Utah, who opposes abortion, also called the ad "a new low" in nomination battles.
"This ad grossly distorts the record of John Roberts from start to finish. It has only one goal: to associate John Roberts with violent extremists," Hatch said in a written statement.
The ad relates to a case involving a group called Operation Rescue, which used aggressive tactics to prevent people from entering abortion clinics.
"Operation Rescue concerned attempts to block abortion clinics from access by patients in hopes that they would decrease the number of abortions," explained former associate deputy attorney general Bruce Fein.
Abortion rights groups brought a suit against the protests under a 100-year-old anti-discrimination law aimed at the Ku Klux Klan. On behalf of the George H.W. Bush administration, Roberts argued that the law did not apply, and in 1992, the Supreme Court agreed.
"It was a very extravagant, in my judgment, use of a statute intended to address the civil rights of minorities to somehow bring to bear with regard to access to abortion facilities," Fein said.
NARAL President Nancy Keenan said her group was trying to take advantage of Congress' recess to get its message out to supporters around the country. The message is now clear, "John Roberts should not be confirmed," she said.
"That he will not protect our personal freedom as women in this country, that the chance of Roe v. Wade being overturned is likely with him on the bench, and those are the reasons that we believe that he does not deserve a seat at Supreme Court," Keenan said.
One Democratic senator, Barbara Boxer of California, wasn't ready to go as far as NARAL yet in openly opposing Roberts, but she did cite the NARAL argument, saying "Roberts sided with some of the nation's most violent anti-choice extremists," and vowed to press the issue of abortion at his confirmation hearing.
"Now Judge Roberts didn't say whether he believes in a constitutional right to privacy during his D.C. Circuit Court of Appeals confirmation hearings. Nor did he directly answer questions about Roe," she said Wednesday to an audience at the Golden Gate School of Law.
To that, Sen. John Cornyn, R-Texas, complained Thursday that Boxer was using a litmus test to determine who she would support for the Supreme Court.
"This litmus test is not only contrary to legal ethics, it is well outside the mainstream of American opinion," Cornyn said, adding that the Senate has established a precedent that during confirmation hearings nominees shouldn't have to pre-judge cases that are likely to come before the court to which they may be seated.
"Erecting conditions to confirmation that Judge Roberts is ethically forbidden to satisfy, as she announced she will do, is not the sort of fair treatment of Judge Roberts that senators from both political parties had pledged to ensure. Justices are not politicians, they don't run on a political platform, and senators should not ask them to do so," Cornyn said.
Click in the box near the top of the story to watch a report by FOX News' Jim Angle.