• by Wendy Davis , September 18, 2026

A new Montana "deepfake" law that requires disclaimers on negative political ads created with artificial intelligence (AI) likely violates the First Amendment, a federal judge said in a ruling issued Wednesday.

U.S. District Court Judge Susan Watters in Helena prohibited the state from enforcing the measure against former state lawmaker Dan Bartel and his political action committee, Accountability in State Government, which had sued to strike down the statute.

The law, passed last year, specifically applies to ads with AI-generated content that "depicts a candidate or political party with the intent to injure the reputation of the candidate or party or otherwise deceive a voter."

The measure prohibits campaigns from running those ads within 60 days of an election, unless they carry disclaimers stating: "This (image/audio/video/multimedia) has been "significantly edited by artificial intelligence and depicts speech or conduct that falsely appears to be authentic or truthful."

The law, which carries civil and criminal penalties, has an exemption for satire and parody, but does not define those terms.

Watters said in a 40-page ruling that the statute likely violates the First Amendment by discriminating based on content as well as viewpoint.

"Enforcement authorities must scrutinize the substance of the image, audio, or video to determine if it depicts a deepfake of a candidate or political party," she wrote. "By targeting and regulating a narrow, specific category of speech, the Act is content-discriminatory on its face."

She added that the law also discriminates based on viewpoint because the restrictions only apply to content that is "injurious rather than uplifting."

The ruling came in a battle dating to May, when Bartel alleged that he faced "imminent civil and criminal prosecution" over election mailers that included a mix of authentic photos and AI-generated images.

For instance, one of the mailers depicted state Representative Llew Jones (who had supported raising gas taxes) holding a gas pump that was shooting out $10 bills.

He sued soon after Jones and two other lawmakers filed complaints about the mailers with the Montana Commissioner of Political Practices, Chris Gallus.

Those complaints were ultimately dismissed by Gallus, who said in court papers filed last month that the mailers were exempt from the law because they were satire or parody. 

Watters said in her ruling that although the complaints that triggered Bartel's suit were dismissed, he was still entitled to an injunction against future enforcement.

"Forcing a speaker to rely on the government's post-hoc, case-by-case explanations of subjective exceptions creates a system of administrative screening that is incompatible with the First Amendment," she wrote. "In this case, while Commissioner Gallus now asserts that the initial mailers constituted permissible satire ... the lack of clear statutory definitions of 'satire' and 'parody' leaves plaintiffs with a valid, constitutionally cognizable fear that their future speech will fall on the wrong side of the line."