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PITTSBURGH (KDKA) — The ACLU has issued an ultimatum to Pittsburgh City Councilwoman Darlene Harris.

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An attorney with the organization says he represents several people who claim Harris blocked them on Facebook, which the ACLU says is a violation of their First Amendment rights.

The lawyer says Harris blocked them after they made negative comments about her, but because Harris is a public figure, it could be viewed as censorship.

Christopher MacTaggart says he viewed Harris’s Facebook page for information pertaining to District One in the City of Pittsburgh.

“I got blocked over something super benign,“ MacTaggart said. “What I got blocked for wasn’t at all inflammatory, it wasn’t profane.”

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MacTaggart is one of four people – constituents of Harris, who were blocked from her page, after posting criticisms of the councilwoman. In particular, from an incident in October, when the councilwoman drove her vehicle through a park on Pittsburgh’s North Side.

Acknowledging that Harris uses the page to post communications and services for those she represents, the letter from the legal director of the ACLU of Pennsylvania reads:

“…excluding people from the platform because they have criticized you is a form of viewpoint censorship, that violates the first amendment of the U.S. Constitution.”

The ACLU wants Harris to respond to the letter by Dec, 4, confirming she’s unblocked her constituents, or they’ll take steps to protect the rights of their clients.

“I think this is a necessary step. A lot of people are going to say this is kind of silly because it’s Facebook, who cares, but the reality of the situation is if a public official uses a medium or a platform- regardless of what the platform is, to communicate with their constituency that makes it a legitimate platform,” MacTaggart said.

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KDKA reached out to Councilwoman Harris for comment. We were told she was unavailable.