The U.S. Department of Justice sued Texas on Wednesday over a new state law that allows Texas police to arrest migrants suspected of crossing the Texas-Mexico border illegally. The lawsuit was filed in an Austin federal court and names Gov. Greg Abbott and Texas Department of Public Safety Director Steve McCraw. It asks the court to declare the state law unconstitutional and prevent Texas from implementing it. The law, which is scheduled to take effect March 5, would make it a state crime to cross the Texas-Mexico border between ports of entry. The new crime is a Class B misdemeanor carrying a punishment of up to six months in jail. Repeat offenders could face a second-degree felony with a punishment of two to 20 years in prison. The law also requires state judges to order migrants returned to Mexico if they are convicted; a judge could drop the charges if a migrant agrees to return to Mexico. This is the second legal challenge to Texas’ new immigration law. In December, ​​the American Civil Liberties Union, the ACLU of Texas and the Texas Civil Rights Project filed a lawsuit on behalf of El Paso County and two immigrant rights organizations — El Paso-based Las Americas Immigrant Advocacy Center and Austin-based American Gateways — asking a federal judge in Austin to prevent Texas from implementing SB 4 and declare it unlawful. Federal courts, including the U.S. Supreme Court, have ruled that immigration laws can only be enforced by the federal government.