ONE IN six people say they know someone who had an intimate relationship with a teacher while at school. A survey of more than 2,200 adults, conducted by YouGov, reveals that 15 per cent know of a relationship between a teacher and a pupil at their school that goes beyond the normal boundaries of teacher-pupil relationships. Only 10 per cent of the population think that it is acceptable for a teacher to have an affair with a pupil.

But this changes once the pupil’s age is specified - 27 per cent say that such an affair is acceptable once the pupil is 16 years old. Men are twice as likely as women to think that it is acceptable for teachers to have an affair with their pupils if the pupil is over the age of consent.

Three-quarters of women believe that a teacher-pupil relationship is never permissible.

Funke Baffour, a clinical psychologist, said: “You can have 22-year-old teachers who would form relationships with 18-year-olds in other contexts,”

she said. “But complications arise in school. I have heard of teacher-pupil relationships that have worked. But that doesn’t mean it’s the right thing to do.”

Emily Arkell, of the NSPCC, said: “Young people can be emotionally vulnerable. If teachers enter into personal relationships with pupils they are taking advantage of this and abusing their position of trust.”

Last month, 29-year-old Jenine Saville-King was cleared of sexual activity with a 15-year-old pupil to whom she had sent 131 text messages in a single day.

In 2005, research by Pat Sikes, of Sheffield university, concluded that around 1,500 pupil-teacher relationships develop every year.