By Susan Schindehette
November 24, 1997 12:00 PM

BY ALL RIGHTS AUTHOR LOIS Duncan should be in a celebratory frame of mind. But she is not. Though I Know What You Did Last Summer, the movie starring Freddie Prinze Jr. and Jennifer Love Hewitt, loosely based on Duncan’s 1973 young adult thriller of the same name, opened as the No. 1 box office hit three weeks running, the movie bears little resemblance to her book. “They made it into a slasher film,” she says of the movie’s mixture of violence and laughs. “And I don’t think murder is funny.”

Tragically, hers is far more than a simple literary critique. Eight years ago, Lois Duncan’s 18-year-old daughter, Kaitlyn Arquette, was gunned down in a drive-by shooting not far from the family home in Albuquerque. And today the case has officially been all but forgotten without a suspect ever having been brought to trial. Minus that final resolution, Duncan, 63, her husband, retired electrical engineer Don Arquette, 66, and their four other grown children can still be counted as the crime’s other victims. “We’ve all had an emotional crisis to deal with,” says Duncan, “and everybody still has nightmares.”

They began around midnight, July 16, 1989, when Duncan and Arquette were awakened by a phone call summoning them to University of New Mexico Hospital. Their daughter, they were told, had been “injured.” “I thought she’d been in a car wreck,” Duncan recalls. “What else could it be?” Then, at the hospital, an ER nurse greeted her, “held out her arms to me and said, ‘Your daughter’s been shot in the head, and you’ve got to prepare yourself for the fact that you may lose her.’ ” Twenty hours later, Duncan’s youngest child, a recently graduated high school honors student who was heading for college in the fall, died from two bullet wounds to the head without ever regaining consciousness.

Six months after Kaitlyn’s murder, police, acting on a telephoned tip, arrested and charged three men with the crime. But in April of 1991, the local district attorney, citing lack of evidence, dropped all charges. Albuquerque police had at first seemed intent on finding Kait’s killer, says Duncan. “They were following up on every lead, doing everything they were supposed to, and we had absolute faith in them. Then, suddenly—wham!—it was this absolute reversal.”

To this day, police, who believe that the three suspects they arrested were in fact guilty of the crime, still maintain that Kait’s death was a random, unpremeditated killing. But for the past eight years, Duncan and Arquette, who moved from Albuquerque to the East Coast to escape the sad reminders of their past, have been digging into evidence that suggests, they maintain, something else. “Why Kait was killed, I don’t know,” says Pat Caristo, a private investigator hired by the family. “But what happened to her that night was not random. Everything is just a little out of kilter.”

According to Duncan, at the time of Kait’s death she was on the verge of breaking up with her boyfriend of the past year and a half, a 26-year-old sporadically employed Vietnamese immigrant named Dung Ngoc Nguyen. But almost immediately after the murder, Duncan also learned that Dung had been part of a crime ring that staged accidents using rental cars, then filed insurance claims for faked injuries—an involvement that he later acknowledged to police. Kait “was young. She was in love,” says Duncan. “But when she realized that something bad was going on, she wanted out.”

Though Duncan and Arquette do not believe Dung was directly involved in the murder (he was never charged in the case), they do think that Kait was on the verge of exposing both Dung and other members of his gang—and that her knowledge of their activities may be what provoked someone to murder her.

Frustrated at what she sees as a lack of follow-through, Duncan began to keep detailed notes on the crime and its investigation, and in 1992 published the nonfiction book Who Killed My Daughter? While Duncan has unearthed no smoking gun in the case, her book recounts what she believes are the investigation’s many loose ends. According to Duncan, there were discrepancies in witnesses’ accounts of Kait’s activities on the night of her murder. Further, she says, a man at the murder scene was never officially questioned. And she is certain that a breezy note initially attributed by police to Kait—and found at the apartment she and Dung had shared in the month before her death—was not in her daughter’s handwriting.

For their part, Albuquerque police maintain that they have pursued all possible leads. The case against the three arrested men never went to trial, they say, because a number of key witnesses recanted for fear of reprisal. “The right people were arrested for Kaitlyn’s murder,” says Capt. Steve Wadley, now head of the Albuquerque Police Department’s investigations division. “Our investigation was reviewed by the FBI, the New Mexico Attorney General’s office and the district attorney. None of them have found fault with it.”

Former Bernalillo County DA Robert Schwartz also believes that the police “dug as deep as they could, until they hit bedrock” but that someday, perhaps in a plea bargain deal with prosecutors, witnesses will come forward with the crucial information that could close the case. In the meantime, he is sympathetic to Duncan’s plight: “If it was my child, I wouldn’t let it go away either. I would bang the drum until something shakes loose.”

Duncan and Arquette know they may never learn the full circumstances of their daughter’s death, much less see a killer brought to justice. Even so, they feel compelled to keep trying. “If the investigation was an honest effort—even without finding out who pulled the trigger—that might allow us to reach closure,” says Arquette.

Until then, says Duncan, there is a single, haunting voice that spurs her on: “In dreams, Kaitlyn tells me, ‘Don’t give up, mother.’ It’s not a matter of revenge. It’s a matter of Kait being worth the truth.”