DALLAS A federal judge in Texas heard arguments on Thursday in a lawsuit brought by two dozen states that seeks to block Obama administration efforts to reduce the threat of deportation for millions of undocumented immigrants.
The case led by Texas and supported by several other Republican-controlled states said President Barack Obama's executive order in November violated U.S. constitutional limits on presidential powers.
U.S. District Judge Andrew Hanen is expected to rule soon on the states' request for an injunction while the lawsuit proceeds.
On Thursday, Tennessee requested to join the other plaintiffs in the complaint against the government, according to court records.
The hearing took place at the U.S. District Court in Brownsville.
The White House has said Obama was acting within his presidential authority when he issued the order.
Obama's plan would let up to 4.7 million of the estimated 11 million undocumented immigrants in the United States stay without threat of deportation, including about 4.4 million who are parents of U.S. citizens and legal permanent residents.
Texas Governor-elect Greg Abbott, a Republican and former state attorney general, said the lawsuit asked for the president's order to be declared illegal and did not seek monetary damages.
"This lawsuit is not about immigration. It is about the rule of law, presidential power, and the structural limits of the U.S. Constitution," the plaintiffs said in court documents.
Earlier this week, a dozen states led by Washington state Attorney General Bob Ferguson filed a brief defending Obama's policies.
Ferguson, a Democrat, said the president's action benefited Washington and other states by improving public safety, keeping families together and aiding their economies.
"Hard working, tax-paying immigrants can now emerge from the shadows," Ferguson said in a statement.
On Wednesday, the Republican-led U.S. House of Representatives approved a Department of Homeland Security spending bill that included amendments that would block Obama's immigration initiatives. The bill next goes to the U.S. Senate.
The amendments would prohibit spending for the president's November order and reverse his 2012 initiative to defer the deportation of more than 600,000 immigrants brought to the United States illegally as children.
(Reporting by Lisa Maria Garza; Editing by Peter Cooney and Lisa Shumaker)