A class-action lawsuit set to go to trial in federal court today accuses the state of Massachusetts of allowing thousands of foster children to suffer a wide range of abuses.

The suit by the New York-based advocacy group, Children's Rights, accuses Massachusetts of "causing physical and psychological harm" to children it was mandated to protect.

It says the abuses include sexual assault, constant foster home uprooting and inappropriate prescribing of psychotropic drugs.

The Boston Globe reports the state will argue it's aware of the problems and taken steps to improve the system.

Opening arguments in the trial are scheduled for Tuesday, January 22nd.

Children's Rights has filed more than a dozen suits against child welfare departments nationwide. Massachusetts is the first state to fight the accusations in court, rather than settle.