In an upset that seemed impossible in June and inevitable by October, Sen. Russ Feingold lost his bid for re-election. Three weeks later, the disappointment lingers for some 1,020,860 Wisconsin voters and at least one ACLU lawyer in Washington. “I’m still in denial,” says Laura Murphy, who first met Feingold in the 1990s and is now on her second tour as director of the ACLU’s Washington office. “I have vivid memories of long conversations with him in the weeks after the 9/11 attacks. He was the only person willing to offer amendments or speak out at all against the USA Patriot Act.”

In 2010, opposition to invasive government security measures is commonplace, even politically convenient. But back then, Murphy emphasizes, it wasn’t. She remembers one member of Congress angrily poking his finger into an ACLU lawyer’s chest. “Do you realize they tried to kill us?” he shouted. “Did you forget they’re attacking us?”

One of the reasons it’s become more politically palatable to attack the government on civil liberties is that Feingold made it so. We sometimes forget that, as well. Most coverage of Feingold’s defeat has centered on the ironic fact that it happened after his campaign-finance-reform legislation was gutted last winter by the Supreme Court. But Feingold is perhaps most famous for being the only senator to vote against the Patriot Act. With his defeat, the civil liberties community now finds itself facing a simple yet daunting task: Find another Russ Feingold.

Feingold will be hard to replace not just because of his expertise but also because of his situation. In the debate over the Patriot Act, for example, Feingold was one of the few senators who seemed to have actually read the bill. In a speech explaining his vote, Feingold argued that protecting civil liberties was critically important in wartime as well as in peace, then warned of provisions that would allow for mass arrests, abuse of material witnesses, wiretaps and warrantless searches, changes to FISA and immigration law, deportation, and indefinite detention. Moreover, because of his (seemingly) safe seat, Feingold was able to take on causes that people with serious presidential ambitions—his were not—crab-walked away from. In 2008 Feingold fought against a provision of a bill that offered amnesty for the telecom companies engaged in illegal spying.

Civil rights and civil liberties activists now need a senator willing to go to the mat on these issues, knowing that he’ll probably lose, yet hoping that he can shave off the worst bits of legislation with savvy and stubbornness. Feingold chaired the Constitution Subcommittee of the Senate Judiciary Committee, and was next in line to take over the Foreign Relations Committee. Just as important, he was able to command the attention of the media. (Watch him explain the implications of allowing the government to listen to your overseas phone calls.) It’s not clear to the civil liberties crowd who can keep this up in the Senate.

In conversations with activists and lobbyists for multiple civil liberties groups, the same small number of possible new Feingolds kept coming up. One candidate is Sen. Al Franken of Minnesota, who has, for instance, spoken out passionately about the civil rights implications of the Supreme Court’s pro-corporate views. At a Judiciary Committee hearing last spring, Franken closely questioned Assistant Attorney for Civil Rights Tom Perez about what the Justice Department is doing to protect gay and lesbian students from harassment at school. Franken sponsored legislation that prevented private defense contractors from enforcing mandatory arbitration clauses for victims of sexual violence.

But Franken also disappointed the civil liberties community with a flip-flop on reauthorization of the Patriot Act in October 2009. People who are passionate on civil liberties issues still cannot explain how Franken could have spoken out so strongly about the bill, then voted to reauthorize it. And Franken—who often prefaces his legal remarks with the warning that he is not a lawyer—may lack the requisite expertise to take up Feingold’s mantle.

So who else? Some activists point to fellow freshman senator Sheldon Whitehouse of Rhode Island. He’s a career attorney who has been an outspoken opponent of Bush’s war on terror policies, including waterboarding. He declassified Office of Legal Counsel memos and railed against the shoddy lawyering that supported those policies. Whitehouse first gained national attention with his lofty rule-of-law statements and razor-sharp questioning during the U.S. Attorney scandal. Like Franken, he’s been outspoken on gay and lesbian rights. He supports gay marriage and opposes the military’s DADT policy.

Like Franken, however, Whitehouse ultimately voted to allow warrantless wiretapping. And neither of the would-be champions has convinced the civil liberties community that he’s as willing to engage in a throwdown as Feingold was.

“I think Whitehouse has a lot of potential,” says Nat Hentoff, the civil libertarian critic who’s now a policy scholar at Cato. “I think Al Franken is Al Franken. He’s good at promoting himself. Feingold has been the only Democrat who’s told the truth of what’s been happening, that Obama has been asking the Congress not to reform the warrantless wiretapping that Bush put in place.”

Others who may slide into Feingold’s shoes include those senators who co-sponsored legislation that sought to remedy the worst civil liberties provisions of the Patriot Act. The Justice Act, for instance, was introduced by Feingold in September 2009. The bill was co-sponsored by Democrats Dick Durbin of Illinois, Jon Tester of Montana, Tom Udall and Jeff Bingaman of New Mexico, Daniel Akaka of Hawaii, and Ron Wyden of Oregon, plus Independent Bernie Sanders of Vermont. For his colleagues, one of Feingold’s virtues was his willingness to lead on these issues, making it easier for them to follow. Now one of them may have to take the lead.

Of course, there is more than one party in the Senate. Caroline Fredrickson, executive director of the American Constitution Society, speculates that civil liberties fights in a Feingold-less Senate might depend more on Republicans like Rand Paul. That’s a promising possibility right now as the sort of people who backed Paul discover a new bottomless pit of anger, this time about TSA pat-downs. But can it be the basis for Feingold-style politics in the Senate? Feingold’s civil liberties record was barely an issue in his failed re-election campaign. When it came up, Feingold’s opponent, Ron Johnson, an Ayn Rand devotee, said he liked the idea of reviewing the Patriot Act but his main concern about liberty was how President Obama was undermining it.

“So much of the Patriot Act exists in law, and they just put it within that law. I certainly share the concerns [about] civil liberties,” Johnson said in June. “Now, if you have Barack Obama in charge versus George Bush—I wasn’t overly concerned with George Bush in power. I’m a little more concerned about the Patriot Act when you have Barack Obama.” What made Feingold unique, and perhaps uniquely credible, was his suspicion of government intrusions on privacy regardless of who was president.

One final note as we enter the Post-Feingold Era of Civil Liberties: In 2006 Majority Leader Harry Reid put Feingold on the Senate Intelligence Committee. It was a way to hold the intelligence community’s feet to the fire on issues of civil liberties and abuses of transparency and accountability. It will be interesting to see which senator is appointed to take Feingold’s place. It will either provide some sense of who in the Senate might now take up Feingold’s cause—or it will confirm the fact that nobody plans to try.

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