GROZNY, Russia — Ramzan A. Kadyrov, the strongman leader of Chechnya, has been at the center of intrigue surrounding the murder of Boris Y. Nemtsov, a prominent critic of the Russian president, Vladimir V. Putin. So before a busy weekend that included a night out with the boys to watch cage fighting, Mr. Kadyrov wanted to clear something up. “I am utterly devoted to Vladimir Putin and ready until the end of my life to resist the enemies of Russia,” he wrote on Instagram.

The question these days is not so much Mr. Kadyrov’s fealty to Mr. Putin, his political patron, but whether Mr. Putin’s Faustian bargain to gain stability in Chechnya, where Russia fought two grisly wars to suppress Muslim separatists, has backfired, unleashing a violent and unpredictable despot.

Critics of Mr. Putin have warned that he has allowed Mr. Kadyrov, 38, to effectively create the Islamic republic that Chechen separatists had dreamed of — albeit one entirely reliant on Moscow for financial support and where Shariah law is selective, not absolute. And, they say, Mr. Kadyrov may now be seeking power and relevance far beyond his base in the jagged hills of the North Caucasus.

Unlike in other regions, where local security forces are subordinate to federal authorities, Mr. Kadyrov controls his own internal security troops, known as Kadyrovtsy. He is known for ruthlessly eliminating critics at home and abroad. And in Moscow, he is widely resented by the security services for being allowed to operate with impunity.