"He was born David Andrew Williams on September 2 in Portsmouth. He grew up and went to school in Portsmouth," Detective Chief Inspector Phil McTavish said.

"It is apparent that he had difficulties as a child, spent a considerable amount of time in care or boy's homes and hostels and was very much independent of his family from early on in his life.

"Observations have been expressed that he was a loner and demonstrated aggressive temper.

"He was convicted of his first criminal offence, a minor burglary, on the 14th of November 1977 when aged 15.

"He has six criminal convictions in the period 1977 to 1984. He was first sentenced to a care order until the age of 18 for snatching a handbag from a woman in August 1978.

About David Lace

"There are four convictions recorded against David Lace subsequent to the murder of Teresa De Simone in December 1979.

"In January 1980 he was convicted of two matters, one being a stolen cash and the other being theft of property from his lodgings on the night before Teresa's murder.

"On the 19th of September he was convicted for the series of burglaries in Portsmouth and received an 18 month custodial sentence and he served nine months in prison at that time.

"On the 8th of June 1984, shortly after his release from custody, he was convicted of a knife point robbery at a post office in Swanwick.

"The circumstances are that he threatened the shopkeeper with a knife, removed money from the till and made his escape. He was chased and detained at the scene. He was sentenced at that time at Portsmouth Crown Court to a total of five years and nine months imprisonment.

"On his release from Dartmoor prison in July 1987 David Lace relocated to Brixham in Devon where he later worked on fishing boats.

"He lived in lodgings in Brixham and we have been able to trace people with whom he worked and socialised.

"It appears that he continued to have little or no contact with his family until the autumn on 1988 when he paid a visit to Portsmouth.

"Family members who he visited at this time gave the impression that he had visited them to say goodbye for some particular reason.

"He made one disclosure at this time to the effect that he had done some bad things in his time, like the post office robbery and also was responsible for killing someone in Southampton when things got out of hand some years ago when he was young.

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"By December 1988 and perhaps significantly at the anniversary date of the murder he was noted by friends and others in Brixham that he had become depressed for some reason and made various disclosures again to the effect that he had done bad things, could no longer cope and appeared to be inferring that he would take his own life.

"He gave away his possessions and gave up his job. He was last scene by friends on the 7th or 8th of December when he again stated that he was leaving and said goodbye to them.

"At 4pm on Friday, the 9th of December 1988 hid landlord, on checking David Lace's room found him dead in his bed.

"He was lying in bed, there was evidence of superficial attempts to cut his wrist, ingestion of painkillers and a plastic bag was over his head.

"The cause of death was asphyxiation and his death was determined as suicide. No suicide note was located or found.

"David Lace was buried in Kingston Cemetery Portsmouth on the 20th of December 1988.