The Interpol-related detention of Kremlin critic Bill Browder in Spain on Wednesday is truly cause for alarm.

Browder, a British businessman born in Chicago, was once represented in Russia by the late Sergei Magnitsky — the attorney who was subsequently arrested and died in a Russian prison from being physically abused and medically neglected. The reason for Magnitsky’s arrest was that he had made allegations of corruption among Russian President Vladimir Putin’s cronies.