ATLANTA -- After bludgeoning his wife and two children to death with a hammer, and just eight hours before slaughtering nine people in the brokerage houses where he traded, Mark O. Barton typed a chilling confession on his computer and warned that he planned to live just long enough to kill "the people that greedily sought my destruction."

The letter, which Barton apparently wrote near sunrise Thursday and then left in the Stockbridge, Ga., apartment where he had killed his family, suggested that he was tortured by his estrangement from his wife, by his losses in the stock market and by unexplained fears that he said had been "transferred from my father to me and from me to my son."

Police in Henry County, Ga., which includes the Atlanta suburb of Stockbridge, released the letter yesterday as the authorities searched for clues to the motive behind Thursday's killing spree, the deadliest in the state's history.

Atlanta's police and political leaders remained grim and devastated yesterday as they reviewed the details of Thursday's carnage. In addition to the eight men and one woman who were killed, 13 people were injured, some of them critically, in the two brokerage houses where Barton sprayed fire with two handguns. Ten people remained hospitalized yesterday.

Because Barton, 44, shot and killed himself in his van as he was stopped by police Thursday night, law enforcement officials said they were unlikely to ever know exactly what caused him to snap.

But the often rambling letter, printed on Barton's letterhead and signed robustly in large script, offered a remarkable glimpse into the twisted thinking of a man who seems to have carefully calculated his three-day rampage.

The letter, along with recollections from people who knew Barton, suggests that the rage that played out on a hot afternoon in Buckhead had its roots in the earliest years of his life. And perhaps, authorities say, he had expressed the rage before.

He was the only suspect in the 1993 bludgeoning deaths of his first wife and her mother. The next year, he was under investigation for possible molestation of his then 3-year-old daughter. In the course of that investigation, a clinical psychiatrist evaluated him as someone who was "certainly capable of homicidal thought and homicidal action."

Barton's mother, Gladys Barton, who lives in South Carolina, released a statement yesterday afternoon saying that she was deeply saddened by the shootings but that she loved her son. "I wish there was some way to explain why this tragedy occurred or some way it could have been prevented," she said.

Barton, a chemist and securities day trader, wrote in his letter that he killed his current wife, Leigh Ann, on Tuesday night and his two children, 11-year-old Matthew and 8-year-old Mychelle, on Wednesday night.

"There was little pain," he explained in the letter, which police said was left on a coffee table. "All of them were dead in less than five minutes. I hit them with a hammer in their sleep and then put them face-down in the bathtub to make sure they did not wake up in pain, to make sure they were dead. I'm so sorry. I wish I didn't."

He went on: "Words cannot tell the agony. Why did I? I have been dying since October. Wake up at night so afraid, so terrified that I couldn't be that afraid while awake. It has taken its toll. I have come to hate this life and this system of things. I have come to have no hope."

Capt. Jim Simmons of the Henry County police said that Leigh Ann Barton moved out of the couple's rented house in Morrow, Ga., in October, and moved into the two-bedroom apartment in nearby Stockbridge.

Three weeks ago, he said, Barton and his two children showed up at the apartment, needing a place to live. Leigh Ann Barton took them in.

Barton wrote that he killed his wife because "she was one of the main reasons for my demise," but then added that he regretted killing her. "She really couldn't help it and I love her so much anyway." He said he then killed his children to exchange "five minutes of pain for a lifetime of pain."

Barton also left handwritten notes on top of each child and his wife, said Chief Jimmy W. Mercer of the Henry County police. Each note paid brief tribute to the victims.

The children had been placed in their beds and covered. A stuffed teddy bear was left on top of Mychelle's body and a Game Boy computer on Matthew's. Mrs. Barton's body was found in a bedroom closet, placed behind boxes and under clothes, presumably so that it would not be discovered by the children, Mercer said. He said the suspected murder weapon, a hammer, also was found.

Barton noted in his letter that investigators might notice similarities between the deaths of his family members and those of his previous wife, Debra Spivey Barton, 36, and her mother, Eloise Powell Spivey, 59, both of whom were found in a camping trailer, bludgeoned with a sharp, heavy blade. But he denied killing them. "There's no reason for me to lie now," he wrote.

Because of the Alabama slayings at a lakeside campground near Cedar Bluff, Barton's dark, troubled side was hardly unknown to the authorities. And several months later, in February 1994, Georgia child welfare officials and the Douglas County, Ga., district attorney's office began an investigation after Barton's daughter, then 3, told a day care worker that he had molested her.

"We were extremely concerned because of the context, that he was the prime suspect in a murder case," said David McDade, the district attorney, who said the reports he read "make me shudder to this day."

Ultimately, nothing could be done to challenge Barton's custody because the child was too young to testify, McDade said. But during the investigation, Barton was evaluated by a clinical psychologist who, McDade said, found he "certainly was capable of homicidal thought and homicidal action."

Suspicion fell on Barton in the Alabama case, investigators said, because he had taken out a $600,000 life insurance policy on his wife four days before her death and because he was already having an affair with the woman who would become his second wife, Leigh Ann Vandiver.

"He was the number-one suspect all the way through and still is," said Richard Igou, the district attorney in Cedar Bluff at the time.

Investigators found traces of what they thought might be blood in Barton's car, but before they could conduct further tests, the chemist told them he had spilled a soft drink on the area, ruining any potential evidence. He gave what they felt were "rehearsed" answers to questions and refused to take a polygraph test, investigators said.

In October 1993, a month after the slaying of his first wife, Vandiver divorced her husband, David K. Lang. A year later, both left their jobs at Lintech, said Julie H. Van Brunt, the company's administrative manager. They were married on May 26, 1995.

They lived in Morrow, a middle-class suburb south of Atlanta, where their house was notable only for the multiple phone lines and banks of computers on which Barton did his work, mostly at home.

But the recent months had been troubled, apparently at least partly because of financial problems due to Barton's losses as a high-risk day trader. As winter came, a neighbor, Cindy A. Northcutt, said the children confided to her that Mrs. Barton had left her husband.

In May, she said, Barton held a yard sale -- but it seemed as though Barton was trying to sell virtually every item of furniture he possessed.

Pub Date: 7/31/99