Lawyer Mr. Julian Hall yesterday slammed rival attorneys for making "thinly-veiled allegations of dishonesty'' against his client, heiress Mrs.

Marion MacMillan.

Mr. Hall spoke out during a hearing to decide how much of her opponents' legal bills she should have to pay after their Supreme Court battle over her home, Perot's Island.

Mrs. MacMillan was taken to court by fellow multi-millionaire Mr. Michael DeGroote after she changed her mind about selling him the island for $8.5 million.

She involved realtors Coopers and the Bank of Butterfield's real estate firm, Betco, in the case, and the trial lasted about eight weeks.

Mr. DeGroote won, and she is now taking the case to the Appeal Court. Coopers are believed to have come to an agreement with Mrs. MacMillan on their Supreme Court legal bills.

But Mr. DeGroote and Betco are asking judge the Hon. Mr. Justice Ground to make her pay all their "reasonable'' costs, well above the standard share normally paid by the loser of a case.

A major plank of their argument is that the Supreme Court trial would not have happened if Mrs. MacMillan had not made an sworn statement on Christmas Eve, 1991.

The statement was "regrettably false'' in four areas concerning Betco, the judge has ruled.

He has also ruled that Mrs. MacMillan's explanation, that she signed what her lawyers put in front of her, "at least negatives dishonesty on her part''.

Yesterday Mr. Hall said everyone had over-reacted to what he jokingly called the "Christmas Eve, post egg-nog'' statement.

Allegations of dishonesty involving the statement came from an "excessively sensitive'' reading of it.

He said the costs demands of Mr. Mark Diel, for Betco, and Mr. John Riihiluoma, for Mr. DeGroote, would have alarming consequences if granted.

Just because someone lost a case did not mean they had to pay "punitive'' costs.

It was speculation that Mr. DeGroote would inevitably have won the case if Mrs. MacMillan had not made the statement.

Mrs. MacMillan had not spent the trial wasting the court's time. She brought important "live issues'' before the judge and came up with a "good arguable case'' at the end of the day.

Some of the issues brought up had been of "substantial public importance''.

He rejected an argument by Mr. Diel that the trial put Betco's reputation at risk by airing serious and unfounded allegations.

All trials affected reputations, said Mr. Hall, and the allegations were not serious. Betco had not been accused of dishonesty, fraud or bad faith.

Mrs. MacMillan had alleged an unintentional breach of duty, stemming from customary local real estate practices.

Granting Mr. DeGroote and Betco what they wanted would "open up a hornet's nest of confusion''.

Mrs. MacMillan should not have to pay such a high level of costs, Mr. Hall said, "unless it's an offence to criticise the Bank of Butterfield or, having changed your mind about the sale of your home, to put forward a host of defences in the hope that at least one of them connects.'' Mr. Justice Ground rejected a claim by Mr. Diel for Betco's costs to be completely reimbursed by Mrs. MacMillan.

The judge said he would give his ruling on what she has to pay "as soon as possible''.

The total spent on the case by Mr. DeGroote and the real estate firms has been estimated at more than $400,000.