By The Associated Press

Missouri’s voter ID law is facing a legal challenge from a national progressive organization alleging it creates undue burdens for voters who lack the required photo identification.

The Democratic-aligned Priorities USA filed the lawsuit on behalf of Mildred Gutierrez, 70, of Jackson County, The Kansas City Star reported .

The law, approved by Missouri voters in 2016, allows a person without a photo ID to cast a ballot if they sign a sworn statement attesting they don’t have required documents.

But the lawsuit alleges that these procedural hurdles are “fraught with uncertainty and unwarranted threats of criminal penalties.” The required statements are signed under penalty of perjury and contain “confusing and threatening provisions that discourage qualified voters from attempting to exercise their right to vote without Photo ID,” the lawsuit claims.