Chechen President Ramzan Kadyrov and his followers publicly threaten to torture Russian journalists and human rights activists and cut off their heads.
They kidnap family members of opponents from other parts of Russia to Chechnya.
They can even murder in the middle of Moscow without any consequences for them: Seven years ago this Sunday, opposition activist Boris Nemtsov was shot dead within sight of the Kremlin.
There is no reasonable doubt that the organizers of the murder came from Kadyrov's immediate vicinity.
Russian laws do not apply to the Chechen ruler in the middle of Russia.
All of this has a lot more to do with Putin's war on Ukraine than meets the eye.
It illustrates the role violence plays in the Russian president's system.
And it reveals his weakness.
Because while Putin is attacking Ukraine with the full force of his armed forces and uttering wild threats against the rest of the world, he doesn't dare put the president of a small North Caucasus republic in his place.
His activities are also uncanny for many in the Russian leadership.
Despite this, Kadyrov is always warmly received in the Kremlin.
Unresolved conflicts are crumbling the Russian state
The war in Chechnya marked the beginning of Putin's rule more than 20 years ago and contributed significantly to his initial popularity.
Externally, the situation there has calmed down.
But none of the problems that caused the conflict have been solved even remotely.
He is kept under cover with a lot of money from the state budget for Kadyrov's private pockets and naked terror.
Below the surface, the conflict is a oozing sore that threatens to disintegrate the Russian state.
Putin is dependent on Kadyrov because he cannot afford to open and clean them.
This would awaken the severe trauma that Russian society has suffered from the bloody fighting in Chechnya and the terrorist attacks in Russian cities.
That would undermine Putin's legitimacy like nothing else.
The fundamental problem, of course, is that Putin knows no other means of resolving conflicts than bribery and violence.
This is evident in his handling of any kind of contradiction.
Both tools can be very effective.
They keep him the loyalty of Russia's elite, who have much to lose, as well as many state-dependent people just eking out a living.
But they have the same effect as the unresolved Chechnya conflict: they are disintegrating the Russian state from within.
Because of the isolation into which Putin has led Russia, there is less and less to distribute, while at the same time contradictions in society are growing.
So, as a result of the violence against Ukraine, Putin will have to use more force in Russia to maintain his rule.
It will also affect what Russia expects once Putin is gone.
The ruler is preparing hell not only for Ukraine, but also for his own country.
And the longer he stays in power, the worse it will get.