A human rights group asked a federal judge Tuesday to force the Treasury Department to release information about whether it blocked millions of dollars in development loans to Haiti.

The dispute dates back to 2001, when international lenders suspended more than $500 million in loans and grants to the impoverished country after President Jean-Bertrand Aristide's party swept to victory in legislative elections that opponents said were rigged.

The Robert F. Kennedy Memorial Center for Human Rights says the U.S. government wrongly told the Inter-American Development Bank to withhold $146 million in loans approved for public health and education in Haiti, the poorest country in the Western hemisphere.

Aristide called the move "genocidal." Eighty percent of the country's 8 million residents lives in abject poverty.

The center filed a Freedom of Information Act request in 2003 seeking documents about the U.S. government's role in blocking the loans. The lending process is not supposed to be political, the center said.

Though international aid to Haiti has since been restored and a new government is in place, the center says it needs to know the motives behind the process.

"There's a precedent for intervention that can stop these loans at a critical point and there's no guarantee this isn't going to happen again," said Monika Kalra Varma, the center's acting director. "We don't think we can effectively battle that today if we don't understand how it happened."

The lawsuit, filed in a Washington federal court, seeks an order forcing treasury officials to comply with the information request.

Neither the Treasury Department nor the Inter-American Development Bank had an immediate comment Tuesday morning.