Donald Trump has been quite clear that he has no intention of releasing his tax returns, despite the norms established by presidential nominees in both parties over the last several decades. That does not, however, mean that the Republican candidate can make the issue go away through his obstinacy.

Late Friday, Hillary Clinton and Tim Kaine both released their latest returns, adding to many years of disclosed tax documents. And while the materials themselves weren’t especially noteworthy, their release renewed interest in the simmering controversy surrounding the GOP nominee’s apparent need for secrecy.

Indeed, the Democratic ticket once again taunted Trump over his refusal to release his returns, asking anew, “What is he trying to hide?”

Team Trump may hope to avoid that question, but the Republican candidate’s running mate may soon complicate matters

Republican vice presidential candidate Mike Pence said on a radio program Saturday that he will release his tax returns soon, amid calls by critics for Donald Trump to do the same. Pence said on WABC radio’s “Election Central with Rita Cosby” that the public would not be surprised by the information in his tax records. “When my tax returns are released it’s going to be a quick read … the Pences have not become more wealthy as a result of 16 years in public service,” Pence, the governor of Indiana, said. Pence said he would release his tax records soon.

That’d be quite a wrinkle, wouldn’t it? How would Trump explain why his running mate felt compelled to honor modern election norms, while he ignores them?

Will Trump now call Pence and urge him not to disclose? And how would that work after Pence’s public vows over the weekend?

In the New York Times this morning, Rep. Mark Sanford (R-S.C.) has an op-ed in which he explains that he supports Trump’s candidacy, but he nevertheless isn’t comfortable with Trump’s refusal to release his returns.

“The presidency is the most powerful political position on earth, and the idea of enabling the voter the chance to see how a candidate has handled his or her finances is a central part of making sure the right person gets the job,” Sandford wrote. “There is a reason a banker wants to see tax returns in determining whether you are eligible for a mortgage. You may talk a good game; tax returns don’t.”