Photo by Getty Images; Illustration by Bloomberg View
Photo by Getty Images; Illustration by Bloomberg View

This weekend will mark the 1,000th day since Mir Hossein Mousavi and Mehdi Karrubi, the two reformist candidates who fought former President Mahmoud Ahmadinejad’s fraud-ridden re-election in 2009, were placed under house arrest. Their detention should end immediately.

There are good reasons for Iran’s new president, Hassan Rouhani, to want to release the two men, and for supreme leader Ayatollah Ali Khamenei to let him. The most compelling for Rouhani is that without the support of the Green Movement that Mousavi and Karrubi represented, he would not be president. Reformist voters expected their leaders to be released in return for their support, and understood Rouhani’s campaign pledge to end the expansion of Iran’s “security state” as a promise to do just that. They are becoming impatient and rightly so. The two men, one held at his boarded-up home and one at an intelligence ministry safe house, are over 70 years old and in poor health.

Releasing Mousavi and Karrubi would also signal to countries involved in talks over Iran’s alleged nuclear weapons program, which restart in Geneva today, that the switch from Ahmadinejad is about more than just style.

Khamenei, for his part, appears to have understood that Iran’s growing isolation under Ahmadinejad has made his regime weaker. Iranians increasingly question the wisdom of a diplomatic posture that makes them poor. In September, Khamenei agreed that Iran’s Supreme National Security Council should decide whether to release Mousavi and Karrubi.

Neither Mousavi nor Karrubi was ever charged with a crime. Ahmadinejad, directly threatened by their claims of a fraudulent election, has gone. So the stage is set.

Despite all this, Rouhani’s choice isn’t open and shut and the odds against an early release remain strong. He’ll have to judge how far he can push the Revolutionary Guard and other regime hard-liners, who oppose reconciliation with the West and consider the Green Movement to be “seditionists.” Both Khamenei and Rouhani will also take a risk in releasing men who have refused to recant their claims to victory in the 2009 polls, and who would be received as heroes once liberated.

Consider the executions -- more than 80 of them -- that followed Rouhani’s election in June. This happened even as the new president was releasing dozens of political prisoners and phoning President Barack Obama, the horn on the Great Satan, to demonstrate how Iran was turning a corner toward moderation. Only last week, a travel ban and suspended sentence were imposed on actress Pegah Ahangarani for her earlier support of Mousavi.

The Iranian regime remains one of the world’s most brutal and repressive. According to a recent United Nations report, Iran still has 500 human rights defenders in jail and executed 724 people in the 18 months from January 2012 to June 2013. Given that record, releasing Mousavi and Karrubi would be no more than a symbol -- but an important one nonetheless.

The U.S. and its allies cannot help by applying pressure. Public intervention for Mousavi and Karrubi would backfire, providing ammunition to hard-liners who maintain that the two men and their supporters are stooges for foreign powers. Still, Khamenei must know he has more to fear from the reaction in the streets of Tehran, should one of these men die in custody, than from freeing them. This is one time that Iran’s supreme leader can gain politically by doing the right thing. Why wait?

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