A MAN convicted solely on the basis of his confessions to the brutal

killing of two elderly women, despite his known false admissions to a

dozen others he could not possibly have committed, was cleared

yesterday.

Three Court of Appeal Judges headed by the Lord Chief Justice, Lord

Taylor, ruled the confessions of David McKenzie, 38 -- referred to by

lawyers as ''a serial confessor, not a serial killer'' -- were totally

unreliable.

They were not supported by other evidence, were unconvincing, and had

been made by an accused suffering from a significant degree of mental

handicap.

Lord Taylor, sitting with Mr Justice Simon Brown and Mr Justice Roch,

then signalled a significant change in the law relating to confession

evidence and ruled that McKenzie's trial should have been stopped.

He announced: ''Cases depending solely or mainly on confessions, like

cases depending upon identification evidence, have given rise to

miscarriages of justice.

''We are therefore of the opinion that, when three conditions (not

corroborated, unconvincing, and mental handicap) apply at any stage of

the case, the trial Judge should, in the interests of justice, take the

initiative and withdraw the case from the jury.''

McKenzie, of Pimlico, London, was convicted at the Old Bailey and

sentenced on March 3O, 199O, for the manslaughter, through diminished

responsibility, of Mrs Barbara Pinder, 76, of Battersea, in 1984, and

Mrs Henrietta Osbourne, 86, of Chelsea, the following year.

The appeal Judges quashed his convictions as ''unsafe and

unsatisfactory''.

McKenzie had been sent to Rampton top-security mental hospital and

remains there despite yesterday's decision, because the Judges rejected

his further appeal against conviction of two arson offences, for which a

hospital order was also made, and he had admitted two offences of

unlawful sex which also resulted in a similar order.

His solicitor, Mr Paul Bacon, said after the hearing he was hopeful

that McKenzie would win his discharge from Rampton soon. He was due to

appear before a mental health review tribunal later this year, and a

hostel had already been found for him.

McKenzie joins a long list of successful appellants, including

Jacqueline Fletcher, Stefan Kizsko, and Judith Ward, wrongly convicted

on confession evidence.

Lord Taylor said in his judgment that McKenzie had given great detail

of the brutal killings of the two women at their homes, which shocked

local residents. Mrs Osbourne, frail and partially-blind, had been

battered, stabbed, and sexually assaulted and her body set on fire. Mrs

Pinder was stabbed 45 times and strangled.

But McKenzie's alleged special knowledge could have been gleaned from

the massive publicity over the killings, said Lord Taylor, and he had

omitted to mention significant details of the killings, including the

fact that a ball-point pen and knitting needle had been used to stab the

women.

Lord Taylor said McKenzie's confessions to other murders could not be

verified. They included killings in Scotland and the North-east, and he

also confessed to the 1984 murder of peace campaigner Miss Hilda

Murrell, 78, in Shropshire.

This last claim was at first taken seriously by the police, but fresh

scientific evidence of semen found on Miss Murrell's clothing now showed

that it could not have been produced by him.

McKenzie's Old Bailey trial for the London killings was conducted

''impeccably'' by Judge Richardson, but he made remarks in his

summing-up which were open to the interpretation by the jury, that a

dangerous killer should not be allowed back into circulation.

The remarks might be regarded as inviting the jurors to decide the

case on the basis of what sort of man they thought McKenzie was, rather

than by considering whether the evidence proved him guilty.

Putting together the doubts over the confessions, the fresh evidence,

and the flawed passages in the summing-up, there was no doubt that the

convictions of manslaughter could not be upheld, said Lord Taylor.

The court would have felt a ''lurking doubt'' about the case even

without the fresh scientific evidence and the criticism of the trial

Judge, he added.