Universities are being urged to hold an urgent review of contracts for part- time staff after a growing number of successful claims for unfair treatment.
A conference for personnel officers and principals heard that not renewing fixed-term contracts leaves them open to claims of unfair dismissal and statutory redundancy pay.
Melanie Tether, a leading employment barrister, said that institutions should consult trade unions on redundancy at the same time as issuing any fixed-term contract. She also suggested contracts for part-time staff could include waivers of their employment rights - a practice deplored by unions but said to be spreading.
"Institutions can no longer afford to be complacent about their part-time lecturers," said Ms Tether, chair of the Industrial Law Society, at the conference organised by Southampton University law faculty.
"The prudent institution will conduct an urgent audit of its arrangements for employing part-time staff with a view to ensuring that they are not treated less favourably than the full-time lecturers with whom they work," she said.
Fractional contracts offer the most watertight protection against claims under equal rights legislation from part-timers, she said, since it puts them on an equal footing with full-time staff.
A variable-hours contract linking pay to the actual time worked is also possible, provided "it does not look like a device to defer employee rights". Ms Tether advised that short-term contracts were appropriate for staff only required for one or two terms in the academic year.
She added: "If the fixed term is for one year or more, the institution can include a provision excluding the employee's right to complain of unfair dismissal if the contract expires without being renewed."
Ms Tether said if the job relied on a single source of funding, other than the funding council, the institution could include a provision saying employment will end if funding is withdrawn.
"A contract of this kind does not constitute a fixed-term contract for the purposes of employment legislation," she said.
Association of University Teachers general secretary David Triesman said the union detected a rise in waiver clauses.
"Each time we have gone to the courts or tribunals and demonstrated there are rights under UK or European legislation, the immediate response from the employers has been to find a way of side-stepping their legal obligations," he said.