Jim Beresford, a Doncaster Rovers director and said to be Britain's highest earning solicitor, and Douglas Smith, from Beresfords Solicitors have denied 11 counts of professional misconduct.

The charges relate to allegations that the pair, aged 58 and 51, failed to act in the interests of their clients by taking cuts of payments made under the Government's coal health compensation scheme.

They are also accused of breaking solicitor practice rules by entering into conditional and contingency fee agreements against their clients' best interests.

Alan Gourgey QC appeared on behalf of the men at a Solicitors' Disciplinary Tribunal in London.

He said: "We say that there is absolutely nothing wrong in a firm earning substantial fees from the conduct of its business.

"At the time when these negotiations were taking place there was considerable uncertainty as to how many claims there would be.

"As matters have turned out it is undoubtedly the case that the level of claims and the success rates were far higher than expected.

"That has meant that solicitors who have invested in being able to manage large numbers of these claims have received substantial fees from the DTI (Department of Trade and Industry)."

The coal health compensation scheme was set up following a lack of safety standards in mines. The scheme led to 750,000 people applying for compensation.

The DTI paid solicitors' fees in successful cases. Beresfords handled nearly 100,000 claims.

Mr Gourgey said less than one per cent of the claims Beresfords dealt with included agreements to take a cut and all those cases were entered into many years ago.

The first hint that the firm had allegedly breached rules came when Beresford received a letter from the Law Society in 2005 - three years after it stopped using such agreements, he added.

The tribunal continues.