It seemed a good sign. Rachel Howarth’s headteacher collared her first thing in the morning and told her he’d just had a phone call from another school about a job she’d applied for. Rachel, an English teacher, had posted her application only the day before. She knew that the school she had applied to had difficulty with recruitment and that she had all the right experience for the job. She also wanted to leave her present school after recovering from a long period of ill health and difficult relations with her head.

“I was very optimistic. I was fully expecting to hear something,” Rachel, 46, says from her West Yorkshire home. But she never heard anything more.

“A couple of weeks later, I opened The TES and there was the job, advertised all over again.”

Rachel - it’s not her real name - will probably never know what was said in that telephone conversation to her head. “You just wonder,” she says carefully. “I was terribly disappointed. It would have been a fresh start.”

There was no point in Rachel asking her head what he had said about her. “There was no way he would have told me,” she says.

She adds: “I think if a headteacher provides any kind of reference, it should be in writing and you should be able to see it. I don’t think it should be permissible for any head to give phone references because of the potential for abuse.”

Phone references are the greyest of areas in the murk of employment testimonials. Unions deplore them, but admit there’s not much they can do about them. Thankfully, their use is not thought to be widespread.

Teachers more often complain about written testimonials. The good news here is that they have more rights than they probably realise.

Some local authorities have a policy of open references. The Secondary Heads Association has also adopted this ethos, recommending to its members that all references they write be open. Classroom unions would like to see this enshrined in law.

But if your head wants to keep the reference he writes about you a secret, what can you do? The 1998 Data Protection Act specifically excludes a right of access to references by your current employer (Schedule 7, paragraph 1), but that’s not the whole story. Turn to the code of practice drawn up by the Information Commissioner, who oversees the implementation of the Act. It’s so new it hasn’t been formally published yet, but it appears on the IC website (details below). Although not legally enforceable, it will carry huge weight with employment tribunals.

It reads: “This exemption (from the right to see your references) does not apply once the reference is in the hands of the person or organisation to whom the reference has been given. The recipient is, though, entitled to take steps to withhold information that reveals the identity of other individuals such as the author of the reference.”

Dave Clancy, strategic policy officer at the commissioner’s office, illuminates: “In most circumstances, we’d say that if someone makes an access request to the recipient of a reference, it should be disclosed.” In other words, your head is not obliged to show how he or she stabbed you in the back, but the head who decided not to shortlist you as a result should allow you to see the bloody knife. Furthermore, Clancy argues that teachers applying for a job within the same authority should in all cases be entitled to see a reference. This is because it is not technically a reference at all but an appraisal, since the prospective and current employers (the LEA) are the same.

Reading your reference, though, may cause new problems. If you don’t like something you see, speak to the head. “It might be a simple correction or a matter of opinion,” Joe Boone, NASUWT assistant secretary for industrial relations, says. “A correction is fairly simple. If it’s a matter of opinion then you could have to start a grievance procedure.”

Graham Clayton, the NUT’s senior solicitor, says: “Referencing is a vulnerable system, because it always has an element of subjectivity about it. If a member comes to us to say a reference is unfair, we’ll support them in investigating it. But in the end, if it comes down to a matter of disputed opinion, our advice will be to name other referees.”

If the way words are used can cause problems, so can a lack of them. Some heads are reluctant to lose star performers or even average ones. An indifferent reference is a sneaky way of deflating escapees’ tyres without actually maligning them. “That’s acting very irresponsibly,” Clayton says. “We do get a smattering of those cases.”

Another reason why heads write short references is fear of legal action. Sharon Liburd, legal officer at the ATL, says: “Some employers write minimalist references to protect themselves. The reference has only to be accurate; if it isn’t, the teacher has a potential claim for defamation.”

Sensible heads therefore do not write anything they can’t back up. References are among the most carefully crafted documents many of them will write - and the most carefully read.

John Dunford, general secretary of the Secondary Heads’ Association and a former long-serving Durham head, says: “You always read between the lines. A reference that says nothing about classroom management, for example, would lead one to suspect that their classroom management was poor.”

Even if the head has slipped nasty comments into a reference, it is not easy for a teacher to mount a case for libel. References are covered by qualified privilege: to prove libel, you must also prove malice. It’s better to mount a claim of negligence to recover lost earnings - but even then you have to demonstrate inaccuracy.

Sometimes teachers just have to face facts: that a lukewarm letter may be what they deserve. “People complain about negative references, but that’s what references are about,” Clayton says. “You can’t generate a legitimate legal dispute out of the truth.”

For the Information Commissioner’s code of practice, visit: www.dataprotection.gov.ukdprdpdoc.nsf Click on ‘Codes of practice our responses amp; other papers’ and follow the link to Employment Part 1.