A Prop 8 fighter is now taking bold swings at the Church of Jesus Christ of Latter-day Saints’ tax-exempt standing.

Rights Equal Rights founder Fred Karger began battling the LDS church in 2008 when the church poured money into a contentious California ballot initiative to ban same-sex marriage. He continued to poke around for eight years, and now he’s hoping to build a case proving tax violations that he can submit to the Internal Revenue Service.

The group produced a television commercial and purchased 60 cable spots for about $2,000 that will air in Utah throughout the week. The ad, which Karger played at a press conference Tuesday morning, features several ex-Mormons asking for help in uncovering the church’s alleged secrets. More specifically, the nonprofit is seeking evidence of tax fraud.

“We are conducting the biggest, loudest, most comprehensive challenge to a church’s tax-exempt status in history,” Karger said.

Tip-submitting information can be found at Mormontips.com. Karger is bracing for a deluge of documents that will demonstrate tax fraud. Expecting to work the case for the next two years, Karger says he currently has no evidence. That hasn’t tempered his expectations. “I’m thinking hundreds of boxes of documents,” he says.

Karger says a leaked 2015 memo spurred this campaign. That document painted same-sex Mormons as apostates, and ruled that their children would have to disavow their parents’ sexuality in order to become full-fledged members.

Karger agrees that the fight is an uphill battle, but he points to a campaign-finance investigation that found the church guilty of 13 counts related to its involvement in Prop 8.

Given sufficient evidence, Karger says the IRS will be compelled to investigate.

“We’re going to be challenging their tax-exempt status on two fronts,” he says, which entail political contributions as well as church-owned properties.

This week already saw a leak of church documents.

A day preceding Karger’s announcement, MormonLeaks posted a batch of four LDS records, including a series of “living allowance” pay stubs belonging to a high-ranking LDS apostle from 2000. The documents indicate Henry B. Eyring earned more than $83,000 that year.

Those documents were never verified by the LDS church. Church spokesperson Eric Hawkins said in a statement that General Authorities sacrifice their careers for full-time church positions when acknowledging they receive a living allowance.

“The living allowance is uniform for all General Authorities,” he said. “None of the funds for this living allowance come from the tithing of Church members, but instead from proceeds of the Church’s financial investments.”