"You're a shit doctor who never listens and I'll be out of here by lunchtime." I had almost forgotten it was Nigel's tribunal today. We were getting on pretty well until today, but I guess his solicitor has been in talking to him. That means we won't be friends for a while, and he will be refusing his medication for at least a week. I try and smile warmly until I remember how paranoid that makes him.

I hate sectioning people. Nigel had to be sectioned because he was going around telling everyone in his council block that they should stop selling crack to their children. He didn't start getting beaten up until he suggested to the parents that they should hand the children over into his care, where he could give them the love they need. It was all very well meant, but you just have to try and work around the fact that people get angry about that kind of thing in the middle of the night.

We all trundle through the corridors to the conference room. Nigel stands, with his solicitor, staring at me. I stand with the nurse and the social worker. The tribunal keeps us waiting for half an hour, until we are called in by the clerk.

They all have cups of coffee, and neat little china plates with biscuits on them. The barrister who is chairing the hearing addresses everyone by their formal title, and we sit on opposite sides of the table: everyone has an expensive leather documents folder and a suit, except for me and Nigel. I feel deeply out of place, and very worried.

"Dr Foxton, are you satisfied that the patient has a mental illness, disorder, or impairment; and that it is of a nature and degree such as to justify detention under the Mental Health Act 1983?" Umm. "Yes," I reply. Confidently. "Yes, what?" I look around. "Yes, your honour?" I smile weakly and start to sweat. Taking my jumper off would look really bad right now.

The tribunal doctor looks over warmly. He is about 70, clearly retired, and being paid by the hour. "When the chair asks you that question, he means: which of the three is it, and under the terms of the Mental Health Act, is it nature, or degree, or both?" I look up at him, willing him to help me out some more. "You have to say which, now."

The chair casts him an evil look. He smiles warmly. "Umm. Illness." I flounder. "And, well, nature and degree, please."

I had never really thought about it. I blush again. Nigel looks baffled, and delighted. The barrister just looks angry and rich.

Nigel's solicitor rounds on me and makes me go through my report. I have to recount, in front of Nigel, all his psychiatric symptoms, in the most technical medical language, because this is a formal legal hearing. It feels as if I am accusing him of a crime: you are charged with stopping taking your medication at home, and hearing voices, and that those voices did compel you to behave very strangely; you are charged with getting into a squabble on a crowded ward with a nasty character over cigarettes, where your understandable misunderstanding of her mental health problems led you to get into a nasty argument and you both being sedated and secluded.

It would feel massively trite and completely counterproductive to mention that he is incredibly charming and funny, and that his delusions and hallucinations are so painfully understandable, in the context of his shit life, that you sometimes feel like giving him a big hug and trying to explain it all as best as you can. Either way, after I read out the list of charges, he will probably never tell me about a single symptom ever again for as long as he lives.

Nigel keeps interrupting to deny these episodes. His solicitor pulls my report apart, implying that I am some kind of sinister jailer.

I think back to our teaching: tribunals are supposed to be inquisitorial, not adversarial. We are supposed to get together and work out what is best. These guys all want to be on Judge Judy. They grill me for an hour, even though there is no way in a million years anyone would let Nigel out of hospital until the medication starts to kick in and gets him back to his normal self. When we start discussing his insight, I deliver what now feels like my trump card - and that thought makes me realise I have sunk to their level.

"He told me, yesterday, that if he got off at the tribunal he would leave hospital immediately and stop taking the tablets." QED. "I never," he shouts. The tribunal retire to consider. But everyone knew the verdict before we even started. The lawyers are a few pounds richer, and a few inches taller; and Nigel and I will have to start from square one all over again.