The state department is facing a new lawsuit brought by Palestinians and Palestinian Americans accusing the agency of deliberately circumventing a decades-old US human rights law to continue funding Israeli military units accused of widespread atrocities in the occupied Palestinian territories.

The lawsuit, which was filed on Tuesday, marks the first time that victims of alleged human rights abuses are challenging the state department’s failure to ever sanction an Israeli security unit under the Leahy Law, a 1990s-era law that prohibits US military assistance to forces credibly implicated in gross human rights violations.

The plaintiffs include Amal Gaza, a pseudonym for a mathematics teacher from Gaza who has lost 20 family members; Shawan Jabarin, the director of the Palestinian human rights group Al-Haq, who endured six years of arbitrary detention in the West Bank; and Ahmed Moor, a Palestinian American with relatives in Gaza who have been repeatedly displaced by the ongoing Israeli offensive. (Moor has written opinion pieces for the Guardian.) Along with two other plaintiffs, they are demanding judicial intervention to force the US to comply with the law.