THE OBAMA administration could not have picked a more inappropriate moment to cut off funding to a watchdog group documenting Iran’s human rights abuses. When Iranians protested the corrupt reelection of President Mahmoud Ahmadinejad this summer, the repressive regime took a lesson from Tiananmen Square and suppressed the popular uprising with force.

This makes it unsettling that the US State Department has turned down a federal funding request by the Iran Human Rights Documentation Center. The group, which has tallied the assassinations of political dissidents and investigated prisoner abuse, will shut down in the spring without grants to continue its vital work.

The State Department had no explanation for turning off the tap that has channeled more than $3 million...