Despite the utter lack of evidence about who poisoned Alexander Litvinenko, the former Russian spy who died last week in a London hospital, it was hardly surprising that suspicion fell immediately on the Russian government and President Vladimir Putin.

Litvinenko was a defector with many enemies in Russia, official and otherwise, and Putin’s record on justice and human rights has left many people prepared to believe the worst. It did not help that the Kremlin quickly went on the defensive. Government spokesmen declared that any suggestion of Kremlin complicity was “sheer nonsense”. Putin could have said something like, “Let us help find out who did this outrageous thing!” That’s also what Putin might have said when Anna Politkovskaya, an investigative reporter, was murdered or when other reformers were killed.

Litvinenko had a long list of highly motivated enemies. He was a defector who claimed he had been ordered to kill the exiled oligarch Boris Berezovsky. He wrote a book alleging that his fellow Russian agents had organised a lethal bombing. At the time he was poisoned, he was said to be looking into the death of Politkovskaya.

But the real problem is that Putin has given no indication that he is dismayed by the political killings, or that he is doing much to stop them.