In the killing of Nemtsov, the trail appeared to lead to security forces and officials close to Ramzan Kadyrov, the strongman ruler of Chechnya who makes a demonstrative performance of his loyalty, regularly calling himself Putin’s “foot soldier.” A Moscow court convicted a handful of Chechen men for the murder, but prosecutors declined to follow the chain of culpability any higher. Similarly, when Verzilov was poisoned, he had been looking into the killings of three Russian journalists in Africa, who themselves had been investigating the private army of Evgeny Prigozhin, a powerful businessman close to the Kremlin and the defense ministry.