Part of a voter fraud investigation against a former Olathe couple by Kansas Secretary of State Kris Kobach ended Wednesday with a whimper.

Steven Gaedtke, 60, pleaded guilty in Johnson County District Court to one misdemeanor count related to unlawful voting.

Gaedtke will pay the maximum $500 fine and court costs. The two other counts against him were dismissed as part of the plea agreement.

“He’s an otherwise law-abiding citizen who made a mistake,” Gaedtke’s lawyer, Scott Gyllenborg, told Johnson County District Judge Thomas Sutherland.

But Trey Pettlon, lawyer for Betty Gaedtke, 61, said he will enter a not guilty plea for her on Thursday. A trial date is set for February. Betty Gaedtke also was charged with three misdemeanor counts related to unlawful voting.

“She maintains she’s innocent,” he said.

Gyllenborg and Steven Gaedtke declined to comment Wednesday after the court appearance.

Eric Rucker, assistant secretary of state, represented Kobach in court on Wednesday. He said afterward that such cases are important.

“You’re protecting the integrity of the voting system,” Rucker said, “and that is a priority of the secretary of state and of the Legislature, which authorized our office to prosecute these offenses.”

The Gaedtkes’ cases stem from votes cast in the 2010 general election. The types of charges and penalties were subject to the laws at the time.

Rucker noted that in the 2015 legislative session, lawmakers increased several categories of unlawful voting from misdemeanors to felonies, which carry more severe potential penalties.

Pettlon said earlier that the Gaedtkes are “very good people” who had been in the midst of a retirement move from Olathe to Arkansas in the runup to the 2010 general election.

The couple applied for advance voting ballots from Johnson County and submitted them and meanwhile were traveling back and forth to move their belongings.

They made a mistake and also voted in the election in Arkansas in person, he said. It was not a presidential year, so they weren’t voting twice for the same candidates.

“They weren’t stuffing ballot boxes or anything,” he said.

Steven Gaedtke is a Vietnam veteran who served in the U.S. Air Force, Pettlon said. Betty Gaedtke volunteers as a domestic violence educator. They built a cabin in the Arkansas Ozarks for their retirement.

The cases against the Gaedtkes marked the start of Kobach’s promised crackdown on voter fraud. Cases from 2010 were chosen because of a five-year statute of limitations.

The Kansas Legislature last session gave Kobach the power to prosecute voter fraud cases, the only secretary of state in the nation with such authority.

Kobach vowed to fight fraudulent voting with tougher registration laws and prosecutions. Critics say voter fraud is rare.