By: KDKA-TV News Staff

PITTSBURGH (KDKA) – A group of families is suing the North Allegheny School District for making mask-wearing optional.

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The new development comes about a month after the school board ended the mask mandate.

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The board voted to let parents decide if their children should wear a face covering in schools, but in a new lawsuit, some parents say the policy jeopardizes their medically vulnerable students.

They’re asking a federal judge to step in, saying North Allegheny’s policy violates the Americans with Disabilities Act.

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It’s not the first time parents have taken legal action over masks at North Allegheny. In August, parents and students filed a complaint to reverse the optional masking policy.