OKLAHOMA CITY, Okla. – Oklahoma State Superintendent Joy Hofmeister and several others are facing criminal charges for allegedly violating campaign laws that prohibit candidates from coordinating with political groups.

Oklahoma County District Attorney David Prater charged Hofmeister and four others involved with her 2014 campaign with illegally coordinating with Oklahomans for Public School Excellence (OPSE), a “dark money” group that placed attack ads against former state superintendent Janet Barresi, KFOR reports.

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Others charged in the case include well-known political strategist Fount Holland, political operative Stephanie Milligan, Oklahoma Education Association Executive Director Lela Odom, and Cooperative Council for Oklahoma School Administration director Steven Crawford.

The case came to light two years ago when prosecutors discovered evidence in an unrelated case involving Chad Alexander, a business partner of Mulligan’s and her fiancé, on Alexander’s computer, the Tulsa World reports.

Those involved in Hofmeister’s 2014 campaign were charged with four counts of accepting contributions in excess of the maximum amount, accepting corporate contributions and two counts of conspiracy for roughly $300,000 that was allegedly funneled through OPSE as independent expenditures.

According to the Tulsa World:

Independent expenditures, as the name suggests, are expenditures made independently of candidate campaigns, mostly notably but not exclusively for advertising.

By law, independent expenditure campaigns may not coordinate with candidate campaigns, because to do so essentially gives the candidate access to potentially unlimited “dark money” — money not subject to the usual campaign limits and not subject to donor-disclosure laws.

Few if any Oklahomans have ever been charged with coordinating dark money and candidate campaigns. But those familiar with campaign law and campaign practices, while reluctant to speak on the record, acknowledge that such coordination is, in fact, not uncommon in one form or another. Emails included in the Hofmeister case charging documents suggest as much, too.

But coordination is difficult to prove, especially with the meager resources generally accorded campaign finance enforcement.

Hofmeister and the state’s Republican Party, of course, insist the state superintendent is innocent.

“At the onset of my campaign I made a promise to myself and my supporters that as a candidate and a public servant I would reflect certain values including transparency, trustworthiness and above all, integrity. I am confident that my actions throughout my campaign more than two years ago were consistent with these values and in compliance with the law,” Hofmeister told KFOR.

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“The Oklahoma Republican Party supports Supt. of Public Instruction Joy Hofmeister. We know her to be of high moral character and support her as she fights these charges,” GOP chairwoman Pam Pollard said.

Hofmeister pleaded not guilty at her arraignment and now faces a Dec. 13 preliminary hearing.

The Oklahoma Education Association – essentially the state’s teachers union – also issued a statement in regards to Odom’s charges.

“In its 127 year history, the Oklahoma Education Association has advocated ethically and honorably for Oklahoma public schools, students, and education professionals,” the statement read. “We are disappointed to see that charges have been filed against former OEA Executive Director Lela Odom, but we firmly believe that when this matter is resolved, she will be cleared of any wrongdoing.

“In the meantime, OEA will continue our work to advance public education for the benefit of all Oklahoma students.”

“I am confident that when all the facts are presented Lela Odom will be exonerated,” Odom’s attorney, Dan Webber, told KOCO.

Barresi, meanwhile, did not have much to say about the allegations against her successor.

“I will let the charge speak for itself,” she told the news site. “I appreciate the diligence and professionalism demonstrated by District Attorney Prater and his staff.”

The state’s Democratic Party on Monday staged a press conference about the case, where party chairman Mark Hammons called on Hofmeister to resign.