An American Civil Liberties Union attorney who represented WikiLeaks source Chelsea Manning has taken aim at his own organization’s decision to represent far-right commentator Milo Yiannopoulos in a free speech suit filed Wednesday in Washington, D.C.

“The ACLU has a long history of representing despicable people in the service of protecting valuable First Amendment principles and in some cases I support decisions that have been made and in other cases I do not. Here I do not,” ACLU lawyer Chase Strangio said in a statement tweeted Wednesday.

“Milo preys on the deep-seated hatred for Black people, other people of color, trans people, immigrants, Muslim people and women that is sadly a central tenet of our social fabric and political system. He is vile. And I am sorry for any platform and validation that he receives,” he added.

SEE ALSO: Milo Yiannopoulos, ACLU sue D.C. Metro transit system

The ACLU filed a federal First Amendment lawsuit on Mr. Yiannopoulos‘ behalf earlier Wednesday after the D.C. region’s transit system barred him from advertising his controversial new book, “Dangerous.”

The Washington Metro Area Transit Authority prohibits ads “intended to influence members of the public regarding an issue on which there are varying opinions,” ads that “support or oppose an industry position or industry goal without any direct commercial benefit to the advertiser” and ads “intended to influence public policy,” among others, according to its own policy.

But as interpreted by the ACLU, WMATA “seeks to sanitize its advertising spaces from messages that might give offense.”

“This case highlights the consequences of the government’s attempt to suppress all controversial speech on public transit property,” Arthur Spitzer, the ACLU’s lead counsel in the case, said in a statement. “The First Amendment protects the speech of everyone from discriminatory government censorship, whether you agree with the message or not.”

Mr. Strangio said, however, the ACLU’s latest client isn’t worthy of its representation.

“Not only do I not condone Milo’s actions, I find him to be a reprehensible person whose contributions to this particular historical moment, in this particular social and historical context, exacerbate the many harms that transgender people, people of color, Muslim people, immigrants and others regularly experience,” Mr. Strangio said.

“Though his ability to speak is protected by the First Amendment, I don’t believe in protecting principle for the sake of principle in all cases,” he added.

Mr. Yiannapoulos, a former Breitbart editor frequently associated with the so-called “alt-right,” first gained notoriety after being permanently banned from Twitter last year for sustained harassment. He later landed a book deal with Simon & Schuster, but the company dropped plans to publish “Dangerous” after an interview surfaced earlier this year of Mr. Yiannopoulos seemingly advocating pedophilia.

“The ACLU could not more strongly disagree with the values that Milo Yiannopoulos espouses, but we can’t allow the government to pick and choose which viewpoints are acceptable,” senior ACLU staff attorney Lee Rowland said Wednesday.

Mr. Strangio, an Northeastern University School of Law alumnus, joined the ACLU in 2013 and currently works for the organization’s LGBT & AIDS Project. He notably represented Manning, a transgender soldier responsible for sharing hundreds of thousands of State and Defense Department documents with WikiLeaks, during her successful bid to receive hormone therapy while behind bars. His views about Mr. Yiannapoulos do not represent those of the ACLU, his statement said.