Andrew Webster’s heart was heavy as he left the school he’d taught at for 10 years for the last time. It felt to him like expulsion, a forced departure when he wanted more than anything to stay. Outside, his students marched in protest; staff and parents had written letters of support and he’d produced reams of documentation for the appeal against the decision, but Webster is 68 years old, three years beyond the national mandatory retirement age, so the Chiswick, London, school’s new management could force him to leave without explaining why.

“It quickly became clear that I didn't have any protection at all,” he said. “My results were as high as ever and I like to think I was still getting better at my job, but suddenly none of that counted for anything.”

For Webster this blow struck at 68 rather than 65 because the school’s previous head teacher had been keen to keep him on. The retirement regulations include a clause that says employers are obliged to consider requests from staff members to continue working when they reach retirement age, but the employer can refuse without providing a reason.

The plight of an estimated 25,000 people who, like Webster, face “default retirement” in the UK each year has been brought to the fore by an important test case at the European Court of Justice. Two years ago, a judicial review brought by Heyday, the membership arm of Age Concern, challenged the legality of the mandatory retirement age, arguing that it contradicted the new Employment Equality (Age) Regulations of October 2006.

The High Court sought guidance from Europe and an official judgment has yet to be given, but last week the Advocate General, Jan Marzak, gave his opinion on the issue. While he agreed that the question of national retirement ages was a matter for European law, he said a mandatory retirement age could be acceptable “if that rule is objectively and reasonably justified in the context of national law by a legitimate aim relating to employment policy and the labour market”.

That means it will now be up to the British government to prove to the High Court that its employment policies justify forcing people out of work at 65 when the case returns there in three months. If the campaigners win, hundreds of workers who were forced to retire will be able to claim compensation from former employers. But where does that leave those going through the process?

According to Age Concern’s Nony Ardill, many are in limbo. “We know of at least 260 cases of people whose employment tribunals are on hold until we get a verdict on this case,” she said. “And there are thousands of others who are approaching their 65th birthdays uncertain of whether they’ll be granted the right to carry on working. Telling someone they have to leave with no reason goes against age-diversity laws.”

Two high-profile cases at Manchester University have highlighted the confusion. Professors Terry Eagleton and Sheila Rowbotham, both world-renowned academics, were told they would face forced retirement at 65 last year. They fought against the decision and last month Rowbotham heard that her request to stay on part-time had been granted. But the decision on Eagleton still stands, and he is considering taking his case to a tribunal.

Mike Saunders, of the recruitment and employment agency Wrinklies Direct, said many of his clients wanted to work beyond the statutory age. “We specialise in encouraging the talents of mature and experienced people and I have many people coming to me who have been forced to retire at 65,” he said. “It seems ridiculous to me. We have a database of candidates and if the best candidates happen to be 68 or 72 then that candidate goes forward.”

Campaigners against a mandatory retirement age say changing social demographics make the rule outdated. “The shape of people’s working lives is completely different now,” said Beth Vaughan at the Employers Forum on Age.

“People have children later, they have elderly parents still alive and kids at university, so it’s complete madness to be told you have to leave your job.”

With one child at university and another still in the sixth form, this is exactly the situation Andrew Webster finds himself in. “I've still got dependants and the small cushion of money we had saved won’t last for ever,” he said. “It’s not a comfortable position. I wish I didn’t have to put myself through the process of applying for new jobs at this stage in my career, but I’m looking for work.”

While they acknowledge the difficulties some individuals might face, the CBI believes a mandatory retirement age is essential. “Employers, especially smaller firms, need a default retirement age so they can plan ahead and allow people to retire with dignity at 65,” said Neil Carberry, the CBI’s head of employment and pensions. “Our survey showed 80% of requests to stay on are granted by employers, so the current system seems to be working.”

Many organisations such as B&Q, Barclays, Halifax and Marks & Spencer, already operate without a retirement age, however. Asda employs almost 8,000 people in their sixties.

“It makes business sense to us,” said the company’s head of diversity, Chris Stone. “Older staff are experienced and loyal. A cynic might say, what’s the point of putting someone intoa management position at 60, but you show me a 35-year-old who will guarantee he or she will stay for 10 or 15 years.”

Lorna Rhodes, 83, is proof of post65 staying power. She continued in her job supervising children with special needs on their journeys to and from school for a decade beyond the mandatory retirement age. Then she found local part-time work caring for the elderly and didn’t retire from that until she turned 80. “It’s so important to keep the mind active and to be involved in life,” she said.

“Being made to stop working before you’re ready can lead to depression and illness; forced retirement probably costs the government more in NHS bills than it would have to spend on supporting people who want to carry on working.”

Webster agreed. “To a large extent you are what you do; you build your life around it. When you’re made to leave and given no explanation, the hidden message is that you’re not wanted anymore. That feels far from dignified,” he said.

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