LUBBOCK, Texas (AP) — Texas Tech on Tuesday asked a judge to throw out fired coach Mike Leach’s lawsuit, saying state law gives the university immunity from legal action.

The university contended Leach is barred from suing the university without a waiver of sovereign immunity from the Texas Legislature.

Attorneys for Leach, who was fired last month amid allegations he mistreated a player who had suffered a concussion, also filed additional claims Tuesday, including that the school violated the Texas Whistleblower Act in dismissing the coach.

One of the attorneys, Paul Dobrowski, said at a news conference that a sovereign immunity defense isn’t permissible under a whistleblower claim. In a statement read by another attorney, Ted Liggett, Leach said he expects to be “vindicated,” and will “vigorously prosecute” his claims.

“I categorically deny that I mistreated Adam James, refused to cooperate with the school’s investigation, or acted in an insubordinate manner as an employee of the University,” Leach said in his statement.

The university wants the judge to take up its claim Jan. 20, before a hearing is held on a motion from Leach’s attorneys seeking to depose Texas Tech administrators — university system chancellor Kent Hance, school president Guy H. Bailey, and athletic director Gerald Myers — and James, the receiver Leach is accused of mistreating.

The attorneys also want documents and communications from the school pertaining to Leach going back to Jan. 1, 2006.

Texas Tech’s filing Tuesday asserts the school is entitled to a sovereign immunity defense on claims made in previous filings by Leach — including breach of contract, slander and libel and violation of due process.

Leach’s attorneys claim in their Tuesday filing that Hance told Leach about Dec. 20 that James’ father, former NFL player and ESPN analyst Craig James, was claiming his son “was being forced” to play before his concussion had healed. Leach denied this allegation to Hance, the filing states.

According to Leach’s filing, the reason for Leach’s dismissal was his seeking a temporary restraining order following his suspension Dec. 28.

A statement from the university said Leach’s newest filing contains “numerous falsehoods and gross inaccuracies.”

“It appears to me this latest filing is nothing more than a desperate attempt to deflect the focus from Mike Leach’s irresponsible treatment of an injured student athlete and Leach’s insubordination,” Bailey, the school’s president, said in a separate statement.