Mrs Lynott told the court she had swapped properties with Mr Tobin
A witness has told the Vicky Hamilton murder trial that Peter Tobin was the tenant of the house in which the schoolgirl may have been killed.
Elizabeth Lynott, 68, told the High Court in Dundee that she and her family moved into 11 Robertson Avenue in Bathgate in 1966.
In 1989 they arranged a house exchange with Mr Tobin and moved to Brighton.
Peter Tobin, 62, denies the abduction and murder of the 15-year-old, from Falkirk, in 1991.
He is also accused of attempting to defeat the ends of justice between 10 February 1991 and 15 December at Bathgate, Edinburgh, Margate and elsewhere, and with concealing Ms Hamilton's body, cutting it in two, and transporting and burying the parts.
Mr Tobin has lodged a special defence of alibi, claiming he was in the Portsmouth area when she disappeared.
Mrs Lynott pointed to the accused in court and identified him as the man with whom she had swapped properties.
The witness was also shown a knife found in the house by police and photographs of it in the loft space.
Mrs Lynott said she had never seen the blade before.
The court also heard from her son and two daughters who were each in turn shown the knife and the photographs.
Each said they had never seen the knife, other than when it was shown to them by police.
The trial also heard evidence from a man who was a tenant and then bought the house in 2001.
James Monteith said he was often in the loft but he too denied ever seeing the knife.
Mr Tobin is accused of abducting Ms Hamilton and taking her to Robertson Avenue in Bathgate, West Lothian, on 10 February 1991, which the Crown alleges was then occupied by him.
The charge also alleges that there or elsewhere he drugged her, struggled with her, compressed her neck, indecently assaulted her and murdered her.
He is also accused of attempting to defeat the ends of justice.
It is alleged that he concealed Vicky's body and removed and disposed of a number of items of her clothing and footwear.
He is also accused of cutting her body in two and wrapping it in coverings and bin bags.
Then, allegedly aware police were conducting a missing persons inquiry, Mr Tobin is said to have put Ms Hamilton's purse under a portacabin to mislead police into believing she had run away from home.
Mr Tobin denies all the charges against him and has lodged a special defence of alibi, saying that between 1700 GMT and midnight on 10 February 1991, he was in the Portsmouth area and was thereafter travelling to Scotland, arriving in Edinburgh at 0630 GMT the following day.
The case, before Lord Emslie, continues.