Read more of our articles on Flint’s water emergency here.

Congressional Democrats representing Michigan asked the U.S. Department of Justice Tuesday to investigate the state’s attempt to block the city of Flint from suing over the ongoing water crisis.

Reps. Dan Kildee, John Conyers, Debbie Dingell, Sandy Levin, and Brenda Lawrence expressed concern that what Michigan is doing “is not only unlawful under state law, but raises serious constitutional due process, equal protection, and associated environmental justice issues,” as they wrote in a letter to U.S. Attorney General Loretta Lynch. “We are writing to ask that you review these constitutional issues.”

State-appointed emergency managers operating under Gov. Rick Snyder (R) in 2014 switched Flint’s water source from Lake Huron to the corrosive Flint River. Now, the lawmakers contend, the state is attempting to use the same emergency manager law to block Flint from taking legal action.

This isn’t the first time the Snyder administration has come under fire on Capitol Hill. Rep. Elijah Cummings (MD), the top Democrat on the U.S. House of Representatives committee investigating the Flint water crisis, in April cast doubt on Snyder’s congressional testimony.

The U.S. Senate passed a $100 million aid package in September but put the onus on Michigan to come up with the other half needed to replace the city’s corroded lead pipes.

Congressional lawmakers are expected to negotiate a final Flint deal as part of a water infrastructure bill when they return to Washington after Election Day.

In the meantime, some 100,000 residents of the predominantly Black city are still being forced to drink, cook with, and bathe their children in bottled water.

“At its core, this predominately African American and high-poverty community has been deprived of all ability to influence the most basic decisions affecting its health and safety at enormous human and economic cost,” the Michigan Democrats wrote in their letter.

Kildee, Flint’s U.S. representative, has insisted that “the state of Michigan should focus on bringing clean drinking water to the people of Flint, not maneuvering to prevent them from accessing the judicial system.”

“Our letter asks the Department of Justice to investigate the constitutional and environmental justice issues implicated by the state’s decision to effectively prevent the city of Flint from suing the state,” Kildee said in a statement to Rewire via email. “Quite simply, this is wrong.”