DES MOINES (AP) — The attorney for one of a handful of Iowa residents charged for allegedly registering to vote when they weren’t U.S. citizens is focusing on a small technicality. Something too small, he argues.

David Richter said Thursday that under state law, Iowa’s voter registration form must have the same size and color of font throughout. But he argues that the text is smaller in the section of the form where residents are asked to sign their names to certify their U.S. citizenship.

“I had a font expert measure it and certify that they violated that section of the Iowa code,” the lawyer explained. “I believe the judge will find the form on its face is illegal.”