Sir Thomas Bingham, who is the senior civil judge, has statutory power to reject or approve rule changes and had been approached for his views by John Edge, a Bournemouth solicitor leading the campaign.
Sir Thomas replied in a letter to Mr Edge, but also wrote to the president of the Law Society, Martin Mears, who wants the higher fees too, asking him to send copies to all members of the society's ruling council. The council will decide whether to back a plan to fix fees by the back door by refusing the society's insurance cover to firms who refuse to put up prices.
Consumer groups argue that the way to deal with shoddy work is to police the profession better, and not to stop efficient firms from undercutting others. The proposed changes would take the cost of conveying a pounds 75,000 house to pounds 625. The Law Society has found that three out of four houses are conveyed for less than pounds 300.
The Law Society faces one of the stormiest meetings in its 200 year history when the issue comes up tomorrow. Dozens of solicitors are likely to converge on the headquarters in London to lobby before the meeting.
Mr Edge has been leading a campaign in recent months to force action over conveyancing fees as low as pounds 150. He claims to have the support of 12,400 solicitors, almost a fifth of the profession. Last night he refused to say exactly what was in Sir Thomas's letter, but said it would not stop the Law Society trying to introduce higher fees.
This summer, in the first contested elections for 40 years, the anti- establishment candidates for president and deputy, Martin Mears and Robert Sayers, pledged to find a way.
They believe they can do it by refusing the Law Society's indemnity insurance to solicitors who refuse to charge the minimum fees. Cheap solicitors would then have to insure themselves on the open market, a far more costly process, and not a genuine option.
A consultation document prepared by Mr Sayers argues that firms which offer cut-price conveyancing are cutting corners and making a disproportionate demands on the insurance scheme, the Solicitors Indemnity Fund. A minimum fee of pounds 250 plus half a per cent of the house price, not including VAT, land registration and searches, is suggested.
Mr Mears will attempt to push the controversial proposals through the council, and if successful ask for comments from the profession, and rulings on the legality of the move.
A fixed scale of fees, enforceable by law, was abolished by the Government in 1972, but fees remained high until the mid-1980s when genuine competition was introduced by the abolition of the solicitors' monopoly on conveyancing and an Act allowing solicitors to advertise.
Mr Mears concedes that the move would not be popular but argues it is not in the consumer's interest to have professionals on the cheap - the public needs to have professions it can trust.
Over the past decade, prices of conveyancing have plummeted. Three quarters of homes are conveyed for less than pounds 300.Reuse content