When Timothy Scott Sherman shot and killed his mother and adoptive father while they slept, the case disturbed the normally quiet life in the small Harford County hamlet of Hickory.
A quarter-century later, another family murder has rocked the county, in neighboring Bel Air. In that case, Robert C. Richardson III has confessed to killing his father, according to authorities.
The state's attorney for Harford County, Joseph I. Cassilly, a gruff no-nonsense lawman, prosecuted the 1987 Sherman case in the beginning of his career and now takes the lead on the Richardson case, which has once again cast a pall over his community.
Both cases not only shocked area residents but have raised many questions, some unanswerable. Sherman and Richardson were both teenagers who went to C. Milton Wright High School and were living in middle-class neighborhoods with their families at the time of the killings.
But while much has been learned about Sherman, who confessed a decade after the crime, the search for answers in the Richardson case has just begun.
No one knows for sure what caused Richardson to allegedly shoot his father, according to investigators who say they are trying to understand his motive. And no one knows for sure what went on in their home. Neighbors say they heard angry shouts from inside for years, though no records or reports of domestic abuse have been made public.
Moreover, it's difficult to understand why.
"I don't know that it's easy to draw a conclusion or comparison from one to the next," Cassilly said of the two cases.
Cases of patricide or matricide are rare — roughly 250 parents are killed each year by their children, or less than 2 percent of all murders in 2010. By comparison, an average of 55 people are struck by lightning a year in the country.
But the subject has been widely studied by academics and forensic psychologists and psychiatrists.
Harold J. Bursztajn, co-founder of the Program in Psychiatry and the Law at Harvard Medical School, said the fundamental question in any case of patricide or matricide is: "Did this happen because the defendant was bad or did this happen because the defendant was mad? And there is a whole spectrum in between."
Children who kill their parents typically do so for one of three reasons, said David M. Reiss, a California-based psychiatrist with 25 years of experience in the field. The children are either psychotic, anti-social, or the victim of severe abuse that is "repetitive to the point that the kid loses track of right or wrong," Reiss said.
Experts say that abuse — physical, sexual or verbal, especially by constant humiliation — is the most common reason for patricide or the less common matricide.
Kathleen M. Heide, a professor of criminology at the University of South Florida, Tampa, and the author of "Why Kids Kill Parents: Child Abuse and Adolescent Homicide," said the most common reason a child kills a parent is because of severe abuse. "That usually can be documented," she said.
The children sometimes have a history of running away, she added. "Typically they killed because they are desperate or they are terrified," she said.
In the past 30 years, Maryland has seen at least five high-profile cases, in addition to Richardson's.
In 2008, Nicholas W. Browning, then 15, killed his parents and two younger brothers as they slept in their Cockeysville home. Browning was sentenced to four life terms.
Lewin Carlton Powell III used a bat to bludgeon his mother to death in their Towson home in 2008 when he was 16. He was sentenced to life in prison.
Michael Edward Joseph Reiriz pleaded guilty to killing his grandparents with a Louisville Slugger in their Guilford bedroom in 1994. He was 31 at the time and received two life sentences.
Lawrence J. Swartz, who died in 2004 at age 38, killed his adoptive parents in 1984 when he was 17. He used a wood-splitting maul to bludgeon his adoptive mother and stabbed her in the neck seven times at the family's Cape St. Claire home. He killed his adoptive father by stabbing him 17 times with a steak knife.
Swartz was released in 1993 after serving about nine of his 12-year sentence. Swartz's case is believed to be one of the first double murders of parents in the United States.
Baltimore County Circuit Court Judge S. Ann Brobst, who was the county prosecutor in the Browning case, said it's difficult to draw conclusions about such crimes from her experience on the case.
"It was totally unexpected," Brobst said. "I think people search for reasons, because people need reasons. You need a conclusion — these things should just not happen. People want an explanation.
"It was, in my opinion, uniquely disturbing."
Sherman was originally imprisoned for two life terms, but a judge in 1999 reduced his sentence. He is up for a parole hearing in about five years.
Sherman, who was 18 at the time of the murders, denied the killings for years. He had claimed that he heard gunshots from his bedroom on the October 1987 night his parents were murdered. Sherman eventually confessed, saying he fired the fatal shots over an argument about the family moving to Florida.
Cassilly said the Sherman case divided the family, between those who believed the teen was innocent and those who did not. Sherman was allowed to attend his parents' funeral at Oak Grove Baptist Church, but he waited in the parlor behind the alter during the service.
Although some in the family were — and continue to be — supportive of Sherman, Cassilly said he sought the strictest sentence possible.
"I see every case as an opportunity to uphold justice," he said. "The guy was a double murderer; I am not sure what else you go for when someone walks in and aims a shotgun at two sleeping people."
Cassilly said in an interview last week that he could provide few details in the Richardson case, including any results from the autopsy or how Richardson allegedly obtained the gun.
Richardson will appear Tuesday for a preliminary hearing in Harford County District Court. The hearing is intended for a judge to determine whether the state has probable cause.
The 16-year-old high school freshman is charged with first- and second-degree murder in the death of his father, Robert C. Richardson, Jr. He also is charged with use of a handgun during a violent crime.
Tom Mauriello, an adjunct lecturer and laboratory instructor at the University of Maryland's Department of Criminology and Criminal Justice, said the case will come down to intent.
"This is not going to be a battle of forensic evidence," he said. "It is going to be a battle of forensic psychology and psychiatry. Was he driven to this? That's going to be the question."
Bursztajn, of Harvard Medical School, said Richardson should receive a comprehensive psychological evaluation for prosecutors to know the circumstances that were at play.
Reiss, the psychiatrist, said much is still unknown. Neighbors near the Richardsons' home on Moores Mill Road said they regularly heard loud arguments, but the Harford County Sheriff's Office said it received no calls for domestic violence or abuse.
"You're looking at severe mental illness or something very wrong in the family," Reiss said. "From the reports, there was a lot of arguing. But you don't know what that means — a lot of arguing that is reasonably resolved, or does it end in humiliation?"
The case of Robert C. Richardson III, who police say confessed last week to murdering his father, Robert C. Richardson Jr., recalls other similar Maryland cases. Since the early 1980s, the state has seen at least five cases of patricide or matricide.
Here's a look:
•May 13, 2008: Lewin Carlton Powell III, 16, uses a baseball to bludgeon his mother, Donna Rosemarie Campbell-Powell, to death in the family's Towson home. The bludgeoning is spurred by a scolding Powell receives over a slip in his grades. He is sentenced to life in prison. An attack on his father, resulting in an attempted murder charge, is dropped in a plea agreement.
•Feb. 2, 2008: Nicholas W. Browning, 15, walks through his Cockeysville home and systematically enters one bedroom and the next with a 9 mm pistol to shoot and kill his parents, John and Tamara Browning, and his brothers, Gregory, 14, and Benjamin, 11, as they sleep. Browning says his parents emotionally and physically abused him and he dreamed of life without them. The judge says he doesn't believe Browning's claims of mistreatment. He receives four life sentences.
•Aug. 14, 1994: Michael Edward Joseph Reiriz, 31, grabs a baseball bat and bludgeons his grandparents, Dr. Walter E.E. Loch and Dr. Mary Hyde Loch, to death. Reiriz claims he was in a rage at his grandfather over his disapproval of his relationship with a woman who was married but separated. Reiriz says he wanted to protect his grandmother from his grandfather and knew she could not stand to live without him. He receives two consecutive life sentences.
•Oct. 12, 1987: Timothy Scott Sherman, 18, shoots and kills his mother, Elizabeth Ann Sherman, and his adoptive father, Stevenson T. Sherman, with a 12-gauge Remington shotgun. He denies committing the murders for more than a decade. He eventually says he killed this parents after an argument about whether the family would move to Florida. He receives two life sentences, but his sentence is reduced and he will be up for a parole hearing in about five years.
•Jan. 16, 1984: Lawrence J. Swartz, 17, stabs his adoptive mother, Kathryn Anne Swartz, seven times in the neck and bludgeons her to death with a wood-splitting maul at the family's Cape St. Claire home. Her body is found naked outdoors in the snow. He uses a steak knife to stab his adoptive father, Robert Lee Swartz, 17 times and leaves the body in a downstairs clubroom. The Swartzes are portrayed as strict and religious parents during the trial. He pleads guilty to second-degree murder and is sentenced to 12 years and serves about nine. He is released in 1993. Swartz marries and has a child. He dies of an apparent heart attack in 2004 at 38 years old.