It is painful to watch what is taking place in Moscow's Khamovnichesky court, where the members of Pussy Riot – Masha, Nadya, and Katya – are on trial. The word "trial" is applicable here only in the sense in which it was used by the inquisitors of the middle ages.

I know the defendant's cage known as "the aquarium" in courtroom number seven well – they made it especially for me and Platon Lebedev [my ex-business partner], "just for us", after the European Court of Human Rights (ECHR) declared that keeping defendants behind bars is degrading and violates the convention on human rights.

This is a subtle and sophisticated way of mocking people who dared to file a complaint with the ECHR: ah, OK, so you say that a cage with bars is bad; well then, here's a cage made of glass, with a little porthole through which you can talk to your lawyers, but you need to twist and contort yourself every which way to actually be able to speak through it. In the summer you feel like a tropical fish in that glass cage – it is hot, and the air from the air conditioner in the courtroom does not circulate through the glass. It was hard for me and Platon to be in the aquarium together the whole day. I can't even imagine how all three of those poor girls manage to fit in there at once.

When they drive you from the detention centre to the courthouse, this is what happens: reveille even before the communal breakfast, stewing in your own sweat while hunched over in the "beaker" [a minuscule isolation cell for special prisoners inside the prisoner transport lorry], transport through the Moscow traffic jams – a minimum of two hours. They held me in the Matrosskaya Tishina detention centre – this is in the city centre; but they bring the girls over from Pechatniki – that is twice as far away. They probably spend three hours in each direction just on travel time alone.

Two humiliating body searches in the detention centre, where you have to strip naked – before departure and after arrival; the convoy conducts another two. A minimum of four body searches a day.

Then they handcuff you to a guard and drag you from the automobile right into the courthouse doors. You've got 10 seconds to turn your head and take a glance at the free world. If you're lucky, you might notice someone you know. That is why it is so important for there to be "greeters" outside the courthouse: every smile of support in this brief instant is worth its weight in gold.

In the courthouse – either straight into the courtroom, at a brisk trot up the stairs, chained by one hand to the convoy guard, or into the "konvoyka" cell – there to wait until they "let you out" into the courtroom.

And in the courtroom – that same aquarium, where you need to react appropriately, to answer questions, and to keep track of the testimony of the witnesses. But how can you keep track of anything in such conditions? The girls don't even have any surface on which to place a notepad in there – take notes "on your lap" for the whole of the court hearing, if your back is healthy enough for that. Otherwise, you hope that your lawyers will write it down, and that you'll then be given the time to discuss what is happening with them.

Recess, a packed dry lunch. What's in it? Dry noodles, dry porridge.

This is not even one of those instant ramen noodle "bricks" – it's worse. By the time the boiling water finally gets the noodles soft enough to eat, the 20-minute recess is over. I stopped eating in the second week of the trial: it was better to survive the day on water alone.

The session has ended, everybody heads home. But the defendants get handcuffed to a guard, and then it's back to the detention centre through the Moscow traffic jams. They arrive after the communal supper. You can take a shower only on Saturday. C'est la vie. The "work day" is 20 hours. Lights out. If there is a court session tomorrow, they'll get you up in three hours and the whole "procedure" will be repeated.

I don't know how the girls endure it.

It is not customary to talk about all this in court, because nobody asks about it in the trial. It is not customary to complain about this in the detention centre, because there this is the usual regime, and besides, if you complain they'll just go and wake you up an hour earlier and bring you back an hour later. But the judge, of course, knows about this regime. Torture, perhaps?

If limiting familiarisation with the case and extending arrest is just the usual run-of-the-mill lawlessness, an 11-hour court session without even a decent lunch break looks like the execution of an instruction to complete the judicial investigation, and maybe even the final submissions, before the end of the Olympiad, while the world's mass information media are busy with other things, and our ignominy does not resonate quite as loudly. The ignominy of a great country, a country of world famous humanists and scientists, turning headlong into a backwards Asiatic province.

I am very ashamed and hurt. And not because of these girls – the mistakes of youthful radicalism can be forgiven – but for the state, which is profaning Russia with its utter lack of conscience.

We have been deprived of an honest and independent judiciary, of the opportunity to defend ourselves and to protect people from lawlessness. But what we can do, if we happen to recognise those who are perpetrating arbitrariness for money and privileges is explain to them and to those around just what we think of them, why we do not respect them, why we do not want to give them any help with anything, and why, on the contrary, we are going to stand against them. That way we shall be able to retain respect for ourselves.

I call on all thinking, good and kind people to send words of hope to the girls. Your support is now very important to those who have ended up in confinement by the will of evil forces.