His school had tried its best to cope with a 14-year-old pupil, but a succession of incidents had pushed its tolerance to breaking point.
First the boy had accused a teacher of sexually abusing him: he said the whole class had witnessed the attack, but none of them backed up his story and the teacher's career was saved. Then he had hit a younger boy in the face and broke his nose. The parents were called in and promised their son would behave. But after three days back at school he was screaming obscenities at teachers and then running out of lessons.
The parents did not come to a second interview and the boy was expelled last Tuesday.
'What am I supposed to do?' asked the head. 'The trendy-wendies in the Department for Education keep going on about the rights of the expelled child. What about the rights of the silent majority of children to be educated in peace?'
Eric Forth, the schools minister, might not have approved. Last week he warned that the number of pupils being expelled was rising and that schools could be fined or forced to publish details of school exclusions alongside exam results in national league tables.
'Excluding a child from school should always be the last resort not the first,' he said. Many schools behaved admirably and accepted responsibility for containing discipline problems, but others were 'all too quick to exclude troublesome pupils'.
The department was unable to supply examples of schools using expulsion as an easy option, and delegates at a National Association of Head Teachers conference in Preston considered the claim a slur. Their rage against the minister was volcanic. 'Forth is a raving lunatic,' said one. 'He has absolutely no idea how schools are run. I just wish he would visit Planet Earth occasionally. I don't care if the department fines me. I don't care if it bankrupts the school. A head has got to be able to maintain discipline.'
Three thousand children have been permanently expelled from their schools since civil servants started keeping records in the summer of 1990 - a quarter for violence against teachers and other pupils, the rest for persistent disobedience. They were sent home, to 'sin bin' special units, or to other schools.
The numbers of expulsions are small in relation to the 105,000 juvenile criminals either convicted of or cautioned for an offence in 1991.
Nigel de Gruchy, general secretary of the National Association of Schoolmasters and Union of Women Teachers, said evidence from his members showed that the problems caused by violent and criminal children were not being taken seriously. 'There would be 30,000 expulsions not 3,000 if this issue was tackled,' he said.
But Mr Forth's impression that the rate of expulsions is rising does seem to be true. Margaret Maden, the chief education officer for Warwickshire, an average county with no special problems, said that the number of children excluded from school had doubled in the past four years.
'The Government's policies, particularly the introduction of a demanding national curriculum, mean that schools have less time and patience when they are faced with a disruptive child,' she said. 'They have also become very wary about getting an image as a difficult school now that they are competing for pupils.
'Ironically, if the Government carries out its threat to put exclusions on school league tables, we may find that schools that are most keen to expel the disruptive may impress parents more than a school that allows them to stay.'
Heads, however, reject all charges that expulsions are being used as a public relations tool or a device to improve exam results. They point out that it is not easy to get rid of a pupil. Governing bodies and local authorities can reverse a decision to expel, and parents have the right to appeal.
The Department for Education found that there were 219 cases of permanent expulsion orders from heads that had been overturned since 1990.
One of these involved a North-west secondary school, whose head did not wish to be identified. 'There was a break-in at the school on a Sunday,' he said. 'A fire was started which wrecked the gym. All the pupils were horrified and the grapevine quickly told me the culprit was a middle-class pupil of mine. The police took him in but, because he claimed that he had dropped a cigarette accidentally, they let him off with a caution.
'The governing body would not accept my decision to expel him and sent him back. It said he came from a good family and should be given a second chance. I still feel terrible. How can I maintain good order and discipline when the pupils know that the only punishment for causing pounds 20,000-worth of damage is a caution?'