For Republicans to block one of President Obama’s nominees is dog-bites-man non-news. For members of the president’s party to defect is more notable. And for Democrats to worry more about their political hides than a nominee’s fitness for service — as happened in the Senate this week — is simply revolting.

The nomination at issue involves Debo Adegbile, chosen to head the Justice Department’s civil rights division. Adegbile was a child actor on “Sesame Street” who grew up to be one of the country’s leading civil rights lawyers. Alongside the Justice Department, he argued the 2012 case in which the Supreme Court eviscerated the Voting Rights Act. Paul Clement, George W. Bush’s solicitor general, called Adegbile “a formidable advocate of the highest intellect, skills and integrity.”

The civil rights post exists in the cross hairs of racial politics; it has been a Bermuda triangle for nominees from William Bradford Reynolds (President Ronald Reagan) to Lani Guinier (President Bill Clinton). Still, with the filibuster for executive-branch positions abolished and 55 Democrats in the Senate, Adegbile’s path should have been clear.

Instead, his nomination died, with seven Democrats opposing him, because of his work on behalf of Mumia Abu-Jamal. This man is a monster — he murdered a Philadelphia police officer — who became, infuriatingly, a cause celebre of the Hollywood knee-jerk left.

Despite overwhelming proof of Abu-Jamal’s guilt, the “Free Mumia” movement took up the case of the former Black Panther as evidence of an innocent man ensnared in a racist system.

Adegbile’s work for Abu-Jamal has been legal — not protesting his innocence but arguing, unsuccessfully, that the prosecutors improperly excluded minorities from the jury and, successfully, that his death sentence was based on unconstitutional instructions. (Abu-Jamal is now serving life without parole.)

As litigation director of the NAACP Legal Defense and Educational Fund, Adegbile signed two friend-of-the-court briefs on Abu-Jamal’s behalf, at the Supreme Court and the federal appeals court in Philadelphia. The Legal Defense Fund then became Abu-Jamal’s lead lawyer and Adegbile signed a brief urging the Supreme Court, again successfully, not to consider reinstating the death penalty.

In the modern media environment, this translated to headlines like’s “Obama Nominates Cop Killer Advocate to Head DOJ Civil Rights Division.” Fox News’s Greg Gutfeld denounced the nomination of a “cop-killer’s coddler” as “a hate crime against our nation’s police.”

The Fraternal Order of Police noted “the tried and true shield behind which activists of Adegbile’s ilk are wont to hide — that everyone is entitled to a defense” but added, “A defense should not be based on falsely disparaging and savaging the good name and reputation of a lifeless police officer.” Yes, except that there is no evidence of Adegbile doing any such thing.

More understandably, Maureen Faulkner, the widow of Abu-Jamal’s victim, wrote, “I would argue that Mr. Adegbile’s decision to defend a cop killer should preclude him from holding any public position.”

This is John Adams and the Boston Massacre meets Willie Horton on the Senate floor — a recipe for senators to do the wrong thing. Which they reliably did.

Adams famously described his decision to defend British soldiers accused in the Boston Massacre as “one of the best pieces of service I ever rendered my country.” Indeed, in private practice, Supreme Court Chief Justice John G. Roberts Jr. represented a Florida death row inmate convicted of murdering eight people. Somehow there was no outcry from conservatives about Roberts’s actions.

A more nuanced argument that Senate Republicans made in attacking Adegbile and distinguishing his representation from Roberts’s is that other Legal Defense Fund lawyers, whom Adegbile was supervising, made offensive out-of-court comments. This seems a strained and tangential basis on which to torpedo a nominee.

There’s blame to spare. The administration flubbed in failing to adequately anticipate and defuse the problem. The 11th-hour flip by two Democrats who pledged support — West Virginia’s Joe Manchin and Arkansas’s Mark Pryor — forced colleagues into a difficult but futile vote. Endangered incumbents including North Carolina’s Kay Hagan, Louisiana’s Mary Landrieu and Alaska’s Mark Begich voted for the nomination and endured news releases blaring about backing “a convicted cop-killer’s most ardent defender.” Others, including Pryor and Montana’s newly minted senator, John Walsh, took the easy way out.

Perhaps most disappointing was Delaware Sen. Chris Coons, whose explanation boiled down to: Adegbile did nothing wrong but I’m voting no anyway, because of a “public campaign by others . . . to elevate a heinous, cold-blooded killer to the status of a political prisoner.” By others?

Obama termed the vote a “travesty.” It’s a sadly fitting word.

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