NEW YORK (CBSNewYork) – Mask gatherings are illegal in New York, with the exception of masquerade parties.

WCBS 880’s Alex Silverman With The Story

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It may be an old law – on the books since 1845 – and it may be obscure, but Paul Browne, the NYPD deputy commissioner for public information, says it’s there for a reason.

Police have used the law five times this week at the protests on Wall Street.

“A couple of people put masks on, and then enter a bank, for example, which three of them did. We caught two. One fled. The police are going to stop them,” he told WCBS 880 reporter Alex Silverman.

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The law was originally put on the books in an attempt to stop uprisings by farmers who used disguises to attack police.

“That has become a worldwide phenomenon when you have people that are declaring war on Wall Street and anarchy that they often cover their faces, not only in this country [but] in other countries. So, we always have to be on top of that because obviously these things have a way of spinning out of control,” said Eugene O’Donnell, a professor of political science at John Jay College of Criminal Justice. “It’s a tool, a device that allows police, in situations like the other day, to try to prevent serious breaches of the peace.”

Obviously, the law is not enforced on Halloween.

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Do you think the law is useful or obsolete? Sound off in the comments section below!