The Association of Personal Injury Lawyers (Apil) has slammed insurers for breaching the personal injury claims protocols, leading to delays and increased claims costs.
The new Apil president Allan Gore said defendant insurers were increasingly withdrawing admissions of liability in personal injury claims.
This was in breach of the pre-actions protocols, he said.
But he admitted Apil had no concrete evidence of how extensive the problem was.
Although the protocols are not enforced for multi-track cases, where the personal injury value is over £15,000, the protocols state that parties "are expected to comply with the protocol as far as possible".
They are mandatory in fast-track cases, those where the personal injury element is below £15,000.
Gore said the withdrawal of admission of liability within fast-track cases was a "breach" of the protocols, and for multi-track cases was "in breach of the recommendation" to follow the protocols.
Gore said an increasing number of cases where the issue of whether defendants could withdraw their admissions were being argued before the courts.
But Forum of Insurance Lawyers president Andrew Underwood said insurers do make concessions as soon as is practicable in a case.
"I am aware of no statistical data of any incidence of admission withdrawal, or failure to admit liability within the three month protocol period," he added.