You're absolutely right when you say that in normal countries the judiciary is the check and balance, the backstop, the way of keeping everything working. Your suspicion is also correct that the judiciary in Russia completely does not function as a normal, independent, law-applying body.
The judiciary in Russia, at every level of the judiciary, from the lowest level right up to their Supreme Court, is corrupt. It's corrupt both on a financial basis and on a political basis. Sometimes people pay money for decisions. At other times, people make phone calls for decisions.
I think that probably the most poignant example of the judicial corruption is again in the Magnitsky case. I'm not just being myopic or self-centred when I say this. In July of last year, a senior judge in Moscow held a trial that ran for about two months in which Sergei Magnitsky was the defendant three years after he died.