He was somewhat of an outsider to this small town straddling a rural highway of antique shops, liquor stores and Cajun-inflected art and music joints.

Those who knew the four Johnson sisters, one of whom was slain Wednesday and another critically knifed on the very lawn where they were raised in Sunset, population 3,000, said Harrison Lee Riley is a former New Orleans resident who’d moved to Arnaudville.

Though he was the women’s first cousin, it seemed unnatural for him to be at their doorstep, arguing with his new spouse and ultimately ensnaring his own distant cousin, Sunset police Officer Henry Nelson, in a fight that ended the lawman’s life.

“Nobody can still answer me that question. Why they were here?” asked Shaterral Johnson, the 42-year-old mayor of Grand Coteau — a town just across the interstate — standing next to crime scene tape Thursday a few yards from where sister Shameka Johnson had been lying under a sheet the night before.

Police say Riley was a “deranged, drug-crazed man,” exhibiting signs of being high on the psychotic drug PCP just after he slashed his 27-year-old wife, Courtney Jolivette-Riley, and stabbed those who intervened: sisters Shameka Johnson, 41, and Surlay Johnson, 34, and their 66-year-old mother, Jacqueline Johnson.

Sometime just before 4:07 p.m., Nelson arrived on the normally quiet block, and Riley stole the officer’s gun and killed him with it, police said. Riley then plowed his car into the interior of the Sunset Mini Mart a few blocks away, where he was finally tear-gassed out of an inner office two hours later, naked.

News of the police officer’s shooting death — the sixth in Louisiana this year — drew some 60 officers and emergency medical technicians from other jurisdictions Wednesday evening, St. Landry Sheriff Bobby Guidroz said, clogging Sunset’s main street in an attempt to aid the tiny, six-officer local police force. Rumors of a hostage scenario bled even into some official law enforcement channels and were later corrected as being untrue.

On Thursday, a more accurate picture of those involved emerged. Shameka Johnson, or “Mickey,” was “a special needs child” who lived with her mother on Anna Street, helped the elderly and loved to travel, Shatteral Johnson said. Surlay Johnson, a certified nursing assistant, intermittently baby-sat Courtney Jolivette-Riley’s young child, but never at their mother’s house, Shatteral Johnson said.

Riley, who “could be a sweet person” when not on drugs, Shatteral Johnson said, was painted as a reckless character in court documents.

Riley, 35, had an extensive arrest history in New Orleans but managed to avoid being prosecuted in several cases. In May 1999, for instance, he was accused of forcing a man to the ground, choking him and robbing him of $120 in the Lower 9th Ward. That case was refused by the Orleans Parish District Attorney’s Office in 2005, court records show, months after Riley had been arrested in New Orleans on an armed robbery warrant out of Houston.

His Houston record includes at least five arrests and one violent act toward a law enforcement agent. In March 2000, he assaulted a peace officer by “striking (the officer) with his hand,” according to Harris County court records.

In 2004, he was convicted of aggravated robbery with a deadly weapon in Harris County and spent about seven years in state prison for the first-degree felony.

In that case, Riley ambushed a man at an apartment complex in north Houston who had asked where he could find beer. According to the police report, the man tried to wrest a gun away from Riley, but Riley fired into the man’s legs.

A police report says the victim asked Riley “why was he doing this.”

“The suspect then shot (the man) several more times,” the report says, “striking the complainant in the ear, legs, throat and on the side of his left cheek,” before sauntering away.

Riley got out of jail in February 2012, said Robert Hurst, a spokesman for the Texas Department of Criminal Justice. On Thursday, the day after the Sunset attacks, Riley was due in a St. Landry Parish court for arraignment on prior charges of cocaine, methadone, morphine and Diazepam possession.

A woman who identified herself as Riley’s grandmother said in a telephone interview that family members were still trying to sort out what happened. “Everyone has something different to report,” she said, claiming her grandson had “never even been in a fight.”

“I’m in another world with this,” the woman added, declining to give her name. “I just don’t understand.”

Sunset’s most visible landmark is a tall, white water tower, planted not far from shops with names like “Bayou Some Stuff.” Its main roadway, crisscrossed with power lines and dotted with churches and a sole Mexican restaurant, connects Opelousas and Lafayette — a 15-minute drive to either city.

The Johnsons’ block was representative of most of Sunset’s residents, who work as schoolteachers, offshore workers or bank employees, said a next-door neighbor named Yvonne Malbrough.

“It’s heartbreaking,” she said from her porch, still wrapped in crime tape, “to see babies that then grow up to be women and then you come back home and see … (them) on the ground dead.”

Sunset Mayor Charles James said he knew everyone involved in the incident, except for Riley. The suspect’s wife, Courtney, was from Sunset, he said, but knocks on the doors of three residences associated with her Thursday yielded none of her family or friends. Court documents show she married Riley last year.

Officer Nelson had served Sunset since 2002, Sunset police Chief Luis Padilla said. Starting salaries on the force are around $1,200 per month, he said.

“We don’t get paid enough, but we’re out there because we love the public,” he said.

Nelson, 52, was “a big, heavyset teddy bear with a smile,” Padilla said. “When he arrested you, he arrested you with a smile.”

The officer still lived in the tin-roofed house with peeling paint where he was reared in Sunset. He had a high school-age daughter but didn’t appear to have a wife or girlfriend, said neighbor Shirley Angelle, who was also his friend since childhood.

“There was never a dull moment with him,” she said.

Surlay Johnson was in critical condition as of Thursday night, while Jacqueline Johnson’s and Courtney Jolivette-Riley’s injuries were described as moderate. Funeral arrangements for Nelson and Shameka Johnson are pending.

Riley, who was booked into the St. Landry Parish Jail, will face charges including several capital offenses that have yet to be determined, St. Landry Sheriff’s spokesman Capt. Clay Higgins said.

“I knew the officer (Riley) murdered, knew his family, he was a kindhearted man. I also personally know the family he attacked with murderous intent. The murder of an innocent young lady, killed in cold blood while she tried valiantly to defend her family, will be a painful loss for our community,” said Sheriff Guidroz, in a statement.

Editor's Note: This story was altered at 8:30 a.m. Aug. 28, 2015, to remove the reference to Riley as a Katrina evacuee.

Advocate staff writer Richard Burgess contributed to this report.