Washington Post reporter Jason Rezaian in a 2013 file photo. (Reuters)

JASON REZAIAN, a journalist who was born and raised in California, moved to Iran in 2008 with the hope of promoting a better understanding of his father’s homeland. After joining The Post in 2012, he wrote about political and economic issues but also took on such subjects as Iranian baseball. He earned the respect of senior officials: Mohammad Javad Zarif, Iran’s foreign minister, has called him “a friend” and “a good reporter.”

Mr. Rezaian nevertheless is scheduled to go on trial Tuesday, along with his wife, Yeganeh Salehi, and a photographer, in Tehran’s Revolutionary Court. Arrested at home July 22, he has been held for 305 days as of Friday in the notorious Evin prison, where he has been subjected to harsh interrogations and suffered through long stretches of solitary confinement.

The Post reporter appears to be a pawn in Iran’s internal power struggles or in the leadership’s attempt to show that a prospective nuclear accord will not alter its enmity toward the United States, or perhaps both. Very little about his case is transparent: His lawyer has been allowed to meet with him only once and said she learned of the trial date through the media.

What is absolutely clear is that Mr. Rezaian is entirely innocent of the charges, including espionage, that have been lodged against him. The State Department and White House, which normally refuse to comment on spying cases, have described the allegations against Mr. Rezaian as ludicrous; President Obama has said that he is guilty of nothing more than “writing about the hopes and fears of the Iranian people.” As Post Executive Editor Martin Baron observed in a recent statement, the charges “are not supported by a single fact.”

As we have observed before, the treatment of Mr. Rezaian raises disturbing questions about a regime that Mr. Obama is counting on to implement a complex and multifaceted accord limiting its nuclear activities. If a U.S. citizen recognized by senior Iranian officials as a reputable journalist can be abruptly imprisoned on spurious charges, what treatment will be accorded the international inspectors who have to determine whether Iran is respecting its commitments? If Mr. Zarif and President Hassan Rouhani either countenance or cannot stop such blatantly provocative behavior by the Iranian intelligence services and judiciary, how can they be expected to overcome the entrenched resistance to limiting Iran’s uranium enrichment?

Since the preliminary nuclear deal was announced April 2, Iranian leaders have engaged in an aggressive campaign to bully the United States and its partners into weakening its terms. Tehran first insisted that all sanctions against Iran must be lifted immediately, notwithstanding an agreement that they would be relaxed gradually as Iran fulfilled its initial commitments. On Wednesday, Supreme Leader Ali Khamenei declared that inspectors would not be allowed to visit military sites or interview nuclear scientists — two essential steps for completing a provision of the accord requiring Iran to explain its suspected work on nuclear warheads.

Placing Mr. Rezaian on trial just 35 days before the deadline for completing the accord looks like yet another attempt at intimidation — one that relies on the blatant abuse of the human rights of an American journalist. If Mr. Khamenei were serious about defusing Iran’s confrontation with the West, he would instead release Mr. Rezaian — and offer him the apology he deserves.