AUSTIN (Nexstar) — Mike Collier, the Democratic nominee for Texas lieutenant governor, sent out a cease-and-desist letter to major news broadcast stations on Tuesday, asking them to stop airing a “false and misleading advertisement” from his opponent’s campaign.

In response to Lt. Gov. Dan Patrick’s latest political ad, which makes claims about Collier and his policy positions, Collier’s office asked broadcasters Tuesday to “be responsible to the community you serve and act with reasonable care to ensure that advertisements published are not false or misleading.” The letter was written by Doyle Dennis LLP, a law firm representing Collier.

In the recent commercial, Patrick’s campaign claims that Collier supports open borders, wants to “ban new charter schools” and wants “boys to compete in girls’ sports” — referring to a political battle over transgender youth participation in sports. The advertisement also claims Collier is a proponent of “AOC’s Green New Deal” and aims to tie the Democrat with President Joe Biden, whose approval ratings remain low in Texas.

Patrick’s ad does not cite any sources to substantiate the claims against Collier as factual. In the cease-and-desist letter, Collier references each claim and includes links to sources, which his attorneys said disprove the advertisement’s statements.

“The latest attack from Dan Patrick is an egregious betrayal of the public’s trust that further demonstrates his desperation in the final days of a failed incumbency,” Erin Mincberg Spiegel, Collier’s senior campaign strategist, said in a statement. “We are disappointed in Dan Patrick’s willingness to lie to the general public, but we are certainly not surprised—it is to be expected from an extremist who has built his career through generating falsehoods, fear, and partisanship. 

Allen Blakemore, Patrick’s top political strategist, is standing by their campaign ad — calling it “effective,” in a statement emailed to Nexstar.

“Mike Collier has proudly proclaimed that he and President Biden are in complete alignment on policy, that there is no daylight between them,” Blakemore said. “He has not disavowed Biden’s destructive policies that are wrecking the Texas economy and putting Texans’ lives at risk.”

This is a developing story. Monica Madden will have a full report on KXAN News at 5 p.m.