At first glance, the Westchester Peace Action Committee Foundation (WESPAC) seems unremarkable: a sleepy community organization with just one part-time staffer, a modest office in White Plains, N.Y., and little by way of public events.

But the group raked in $2.4 million in 2022—more than three times as much as it raised in 2020, according to public tax filings. The charity in 2022 spent nearly $1.5 million on "office expenses," a category the IRS says should only cover "supplies, telephone, postage." ...

In May, families of the victims of Hamas's Oct. 7 attack on Israel filed suit against National Students for Justice in Palestine and American Muslims for Palestine, both of which, the plaintiffs allege, are "collaborators and propagandists for Hamas." Buried in the suit is a brief reference to WESPAC, which the suit names as the "official 'fiscal sponsor'" of National Students for Justice in Palestine.