ACLU calls for investigation of Operation Lone Star

Gov. Greg Abbott might soon be battling the federal government over the state's controversial anti-immigration initiative.

Driving the news: The American Civil Liberties Union filed a formal complaint with the Department of Homeland Security on Monday, asking the federal government to investigate the way migrants are treated under Operation Lone Star, Abbott's $4 billion border security push.

• Earlier this week, the state started busing migrants from the border to New York City, which New York's mayor called "horrific."
• The other side: Abbott said he hopes the mayor of New York "follows through on his promise of welcoming all migrants with open arms so that our overrun and overwhelmed border towns can find relief."

Why it matters: It's not clear if the state has the legal authority to transport migrants to the border — or other states — since immigration enforcement usually falls under the purview of federal authorities.

The big picture: The ACLU alleges that DPS agents are overstepping their legal authority by detaining and transferring migrants to DHS custody and its Customs and Border Protection agency, according to the Dallas Morning News.

• The five-page ACLU letter asks the DHS to stop migrant transfers by Texas DPS, and to end "any detention of migrants on federal property by Texas DPS."
• The ACLU also says this summer's heat wave exacerbates concerns, noting that holding people outside for several hours increases the risk of heat stroke.

The intrigue: Abbott might be hoping any ensuing legal battle makes it to the U.S. Supreme Court, which would raise his own national profile and give the high court a chance to overturn a decision in a 2012 Arizona case that placed restrictions on states in immigration enforcement.

Between the lines: The fight over immigration enforcement and the line between state and federal jurisdictions will be a key issue in the 2022 elections.

What they're saying: "Texas DPS officers do not have the authority to engage in immigration enforcement and, therefore, have no standards for holding people," Kathryn Huddleston, a staff attorney with the ACLU of Texas, told the DMN.