On the afternoon of Dec. 18, 2000, Kirsty MacColl, 41, was scuba diving with her two teenage sons in a federally-protected marine park off limits to large boats when a prominent Mexican executive's yacht entered the area. Kirsty was killed instantly in the boat's propeller.

Last month, in her first trip to the country where her daughter was killed, Jean MacColl, 80, demanded that Mexican authorities reexamine her daughter's wrongful death case, a case she believes was clouded with corruption. And she insisted that officials improve law enforcement so that other mothers won't have to live her nightmare.

Jean MacColl's trip began with a memorial ceremony in Cozumel, the Caribbean island 12 miles from the Yucatan Peninsula, which is popular among travelers for its clear turquoise waters. From a boat above the spot where Kirsty was killed, Jean and friends released a wreath into those waters with a ribbon that said, "Goodbye to an angel."

"We said goodbye to Kirsty," Jean MacColl told The Herald in an interview in her hotel room in Mexico City a few days later. "But though it was very nice, it didn't close the book."

MacColl said she felt she had no choice but to come to Mexico to seek closure, something she never found in London. Since her daughter died, she had never been contacted by the Mexican government or by the business magnate who owned the boat, she said.

"In three years, nobody gave me a word of condolences -- certainly not Gonzalez Nova," she said, referring to Guillermo Gonzalez Nova, who was on his boat with his two sons, a daughter-in-law, a baby granddaughter and a deck hand when the accident happened.

Gonzalez Nova is chairman of Controladora Comercial Mexicana, Mexico's third-largest retailer. The company owns more than 200 supermarkets and restaurants throughout the country, including Sumesa supermarkets, Mega superstores, Bodega discount warehouses and the California restaurant chain.

The executive did not return calls made to his office in late March. His secretary said he would be out of Mexico until May.

Deck hand Juan José Cen Yam of Cozumel testified that he was driving Gonzalez Nova's Bertram power boat during the accident that left Kirsty MacColl dead and one of her sons wounded. Cen Yam, an employee of Gonzalez Nova, was convicted of the wrongful death of Kirsty MacColl. He received a jail sentence of two years and 10 months, a sentence that was commuted after he paid a fee of $1,900 pesos (about US$180), one peso for each day of jail time. He was also required to pay Kirsty MacColl's sons a reparation of 25,280 pesos (about US$2,300), an amount based on the minimum wage in the state of Quintana Roo.

The court sentencing document states that Cen Yam, then 28, was not properly certified to drive the boat and that he had allowed someone to recline on the boat's windshield, thereby blocking his view.

MacColl and her supporters are not convinced that the case revealed the truth.

"We believe that Gonzalez Nova and his family have exerted undue influence to affect the outcome of the case," said human rights activist Fred Shortland, a member of the Justice for Kirsty campaign, which counts U2's Bono among its supporters.

UNCERTAINTY AND TRAGEDY Mexican law does not allow Kirsty MacColl's case to be reopened, so Jean MacColl is requesting a new trial. On March 12, she submitted a file to the federal prosecutor's office in Cozumel that shows new evidence and highlights conflicting testimony in the original trial, said her lawyer, Demetrio Guerra. It is too early to tell whether a new case will be tried.

According to court documents obtained by The Herald, the accident scene described by those aboard Gonzalez Nova's boat, "El Percalito," is entirely different from the one described by other witnesses.

Those on the boat testified that it was traveling at a speed of 1 knot. The other witnesses said the speed was 20 knots. The area's speed limit is 4 knots.

Those on the boat said there was no sign that people were scuba diving in the area. The other witnesses said it's a well-known scuba diving zone.

Those on the boat testified that Cen Yam was driving. At least one witness testified that it couldn't have been Cen Yam because he was in the back of the boat.

What is not disputed is that at around 2 p.m., Kirsty MacColl was scuba diving with her sons, Louis and Jamie, then 14 and 15, in the Chankanaab coral reef, which is filled with brightly-colored tropical fish. The trio, along with a scuba guide, had just resurfaced after a half-hour of underwater exploration.

The boys heard a scream telling them to watch out. The ocean water became tinted red with blood. The boys looked up and saw their mother's body floating face-down in the water, cut nearly in half.

A LIFE CUT SHORT Kirsty MacColl was born in 1959, the daughter of choreographer Jean Newlove and British folk singer Ewan MacColl. Her musical career began as a teenager with a punk band called Drug Addix. She later embarked on a rocky solo career, and she also did backup vocals for Van Morrison, Talking Heads, the Rolling Stones and others.

In a 2001 TIME magazine article, Ed Grant wrote that Kirsty was "a bona fide enigma: an immaculately talented artist who achieved a certain level of notoriety in her native England but still couldn't find a recording label in the late 1990s. Here in the United States, her sole claim to fame was having written Tracey Ullman's hit 'They don't know.' " Kirsty MacColl's mother and family friends described her as a witty, funny woman who was a devoted mother and friend.

"It's rather ironic that we're seeking justice for Kirsty because she was actively involved in seeking out justice for others," said Charles Dickins, a family friend who was with Jean MacColl in Mexico.

Jean MacColl came to Mexico without any appointments, but was able to meet with an aide of President Vicente Fox at Los Pinos, as well as with officials at the Tourism Secretariat, the Foreign Secretariat and the British Embassy, she said.

"We really came on a wing and a prayer," MacColl said. "But since I've come here, authorities of all levels have expressed real regret and sympathy. One feels very optimistic that something will be done." A SIGN OF CHANGE Emilio Goicoechea, subsecretary of tourist operations for the federal Tourism Secretariat (SECTUR), said he is working with the Secretariat of Environment and Natural Resources (SEMARNAT) to place buoys around protected natural areas to indicate that boats should not enter.

He also said he plans to work on better enforcement of boating laws in tourist areas, although much of the change will come through education.

"We can't have police roaming these areas all day -- they are too large," the former congressman said. "We are going to have to inform people about where boats can go and ask people to report violations."

According to the regulations of the Chankanaab reef, which was designated a protected natural area by a 1996 presidential decree, the only types of motor boats allowed in the area are small ones such as those used to carry scuba divers. In no case may a boat enter the area if its draft (the depth its keel protrudes into the water) exceeds two meters. Guillermo Gonzalez Nova's boat drafts more than two meters, said Guerra, the MacColl family lawyer.

Although SECTUR is not directly involved in Kirsty MacColl's case, Goicoechea said that there is little the MacColl family can do now to seek justice.

"They should have been involved in the process since the beginning, to make sure justice was done," he said. "Nobody was representing the interests of the family, and now we have a result that doesn't suit any of us."

Now that Jean MacColl and her supporters are back in England, they hope the Mexican officials keep their promises.

"We accomplished everything we came (to Mexico) to do and more," said Shortland of Justice for Kirsty. "Now it's just a matter of seeing how to maintain this momentum half a world away."