Kirsty MacColl's mother campaigns to discover truth of singer's death

The mother of the singer Kirsty MacColl, who was killed in an accident almost three years ago, will travel to Mexico next month to confront the man she believes is responsible for her daughter's death.

Jean MacColl, a choreographer, has spent the past three years attempting to clear up the mystery surrounding the events that led to her daughter's death. She was hit by a speedboat while diving with her two young sons in a marine nature reserve off the Carib-bean resort island of Cozumel in December 2000.

The boat, a £127,000 craft, the Percalito, which crashed into the singer, was owned by Guillermo Gonzalez Nava, the boss of one of Mexico's biggest supermarket chains, Comercial Mexicana, and one of the country's richest men.

Only divers' support boats are permitted in the area where MacColl, who would have been 44 last week, had just surfaced after exploring the Chankanaab reef, a popular destination for British visitors.

Jean MacColl revealed that private investigators working for the family have allegedly discovered attempts by authorities in Mexico to manipulate the statement made by the divemaster who had been supervising the singer's trip on the day she was killed.

She said: "After signing one statement for the port authority captain, he was then called back by another captain and asked to sign a blank piece of paper. To me, that smacks of criminality." The new findings add weight to Mrs MacColl's claim that justice has not been done. In March this year, an employee of Mr Gonzalez Nava, Jose Cem Yan, who was apparently at the controls of the boat when it hit the singer, was found guilty of homicide after a hearing in Mexico.

Mrs MacColl says Mr Gonzalez Nava lied in court. "He said the boat was only going at one knot. If it was, it would have gently pushed the divers out of the way. Witnesses say it was more like 20 knots." Cem Yan was sentenced to two years and 10 months but was allowed to go free after paying a fine of just over 1,000 Mexican Pesos (£70).

"Gonzalez Nava was on that boat with his family, including a baby. He was the only person licensed to drive it," claimed Mrs MacColl. "He has never expressed regret for what happened. I want to speak to him as a parent and ask him to tell me the truth."

The singer's two sons, Jamie and Louie, support their grandmother's mission and say they need to know the truth. Speaking for the first time yesterday, to The Independent before the annual meeting at the Kirsty MacColl memorial bench in Soho Square, London, Louis MacColl Lillywhite, 17, who was also hit by the Percalito, said that he appreciated the support from his mother's fans who placed yellow roses and a birthday cake on the bench before taking out several guitars and singing some of her hits.

"It all helps me remember my mum. The singer Bono sent me a message telling me that he lost his mum at about the same age - about 14 - and that he'd pretty much forgotten who she was."

At yesterday's meeting, Jean MacColl also launched a letter campaign calling for a judicial review of the case and for legislation to provide improvements in all the divers' safety procedures in Mexico.