From police departments to child protective services, the parole board to the Social Security Administration, Weston eluded - and sometimes exploited - each one.
"How did she manage to get away with it?" said Robert Sanabria, whose brother Edwin was one of Weston's captives. "How did they let her roam free?"
Everyone is trying to answer those questions.
City detectives, the FBI, and law enforcement in six states are still trying to sort through the twisted life of Weston, 51. She was arrested Oct. 15 after four mentally disabled adults, including Sanabria, were found locked in the cellar of a Tacony apartment house.
With three others, she was charged with multiple counts of kidnapping, conspiracy, false imprisonment, and assault.
From 1987 to 1993, Weston was supposed to be under court-ordered supervision and receiving psychiatric treatment as part of her parole for a 1984 murder conviction.
But she hid from parole officers.
"This woman was in absconder status for five years," said Leo Dunn, a spokesman for the state Board of Probation and Parole. "Looks horrible."
Weston is accused of stealing the Social Security checks of the four people locked in the Tacony cellar. Constantly on the move, she traveled with an entourage that included her boyfriend, Gregory Thomas; her daughter, Jean McIntosh; and a self-proclaimed minister, Eddie Wright. All have been charged.
Authorities have taken eight children into protective custody, some of whom were being cared for by Weston. The four adults from the basement have been placed in the city's care.
Weston's lawyer, Michael J. Graves Jr., did not respond to requests for comment.
Weston was convicted in 1984 of third-degree murder for starving her sister's boyfriend, Bernardo Ramos.
And yet, when she was arrested Oct. 15, she maintained responsibility for several children who were not hers, including her niece, Beatrice Weston, 19, who suffered abuse so severe police were surprised she survived.
Sources close to the case said that, in addition to defrauding disabled people of government checks, it appears Weston may have created a "breeding factory" - having babies herself and even forcing others to do so, to generate more benefits.
On Thursday, Family Court ordered DNA testing on all the children taken into custody. Police said it remained unclear who their parents were, but it was assumed they were related to Weston and her alleged accomplices.
"This rivals in its horror the Gary Heidnik case," said former District Attorney Lynne Abraham, referring to the North Philadelphia torturer who held five women captive in his basement and killed two.
"What we need to ascertain now," she said, "is how something so unspeakably horrific happened out of the view of everyone who was supposed to be mindful of these people's interests."
Among areas of questioning:
Child protective services
Weston was sentenced to 4 to 10 years, with time served, for starving Ramos, 25, in the coat closet of a North Philadelphia apartment. At the time, her four children were assigned to a DHS case manager who took one of her children on prison visits to see his mother, as one of her sons recalled last week.
When she got out of prison in 1987, a Family Court judge gave her custody of three of her children, according to her younger brother. A fourth son went to live with an uncle.
The brother said Linda Weston's murder conviction was not raised during the hearing in 1990. The judge simply ordered a series of supervised visits before Weston could get her children back.
"I remember asking: 'How in the world did that happen? How did she get any of her kids back?' " said her brother, who asked to remain anonymous because he is still trying to put his past behind him.
"Nobody questioned her ability to take care of them," he said. "They didn't bring up anything in regards to abuse or murder."
Experts say any adult seeking custody of a child is supposed to have a full background check by DHS, with a criminal-background check.
DHS must then present that information to a Family Court judge in a hearing.
Weston subsequently had at least four other children with one of the men arrested, Gregory Thomas. They range in age from 14 to 18.
In addition, Weston took her niece Beatrice from her mother, Vicky Weston, according to relatives.
When Vicky Weston tried to get her daughter back, Linda Weston told her she had legal custody. She later took off with the teenager.
Alicia Taylor, a DHS spokeswoman, said the department was restricted by state law from discussing the situation.
"We are absolutely searching our records to see what, if any, involvement we have with this family," she said.
Weston repeatedly violated her parole for her 1984 murder conviction. But each time she was cited, the parole board put her back on the street.
During her trial, her mental stability became an issue. While judges debated her competency, she had been committed to a state mental institution.
Court-ordered psychiatric evaluations found her to be "mildly mentally retarded" and suffering from "intrinsic brain damage, namely epilepsy." She was also diagnosed as schizophrenic, court records show.
On Jan. 15, 1987, Weston was paroled. As a condition, she was required to undergo "intensive care" with psychiatric therapy and to take antipsychotic medication as long as prescribed, records show.
Weston quickly violated her parole. On July 8, 1987, she had another parole hearing.
Again, she was released with the same order to undergo supervised intensive care and to take medication.
But on Oct. 10, 1988, Weston was declared delinquent because she had not been reporting to her parole officer, who never saw her again.
Dunn, of the Board of Probation and Parole, said he could not detail what happened, because of sketchy records.
Department of Corrections spokeswoman Susan Bensinger said that if the parole board had ordered Weston returned to prison, she would have had psychological evaluation. If necessary, Bensinger said, Weston could have been kept in a mental-health facility until 1993.
Weston had been in motion for years, moving from Norfolk, Va., to Killeen, Texas, to West Palm Beach, Fla., and back to Philadelphia on Oct. 3.
Along the way, neighbors and even relatives sent up warning flares.
At the house where she was staying recently in West Palm Beach, neighbors said they had seen people from the house who appeared to have been injured, with busted lips and cutup faces.
Chase Scott, a spokesman for the West Palm Beach government, said that police responded to complaints, but that Weston eventually picked up and left.
In 2005, the parents of one of the victims found in the Tacony basement - Tamara Breeden - filed a missing-persons report with Philadelphia police.
Then in 2009, a close relative of Weston's said he filed a complaint with the police department's special victims unit, alerting authorities to the fragile, malnourished condition of Beatrice Weston.
The girl was curled on the floor in a corner of a room. Her hair was falling out, she was extremely thin, and she was too weak to talk.
The relative said he spoke to a detective and filed a formal complaint. Police showed up at the house, but, according to Vicky Weston, told her the matter would have to be settled by the courts.
Soon after, Linda Weston vanished, taking her niece with her.
Police and other officials have not commented on the involvement of DHS or other city agencies in Beatrice Weston's case, but Mayor Nutter said a full inquiry was under way.
Vicky Weston said a Family Court judge granted Linda Weston partial custody of her daughter in 2003 because Vicky Weston was recovering from a head injury. She said her sister's criminal past was not raised until a 2004 hearing, when Vicky Weston brought it up herself in an attempt to get her daughter back. Soon afterward, Vicky Weston said, Linda Weston disappeared with Beatrice, and authorities told her the case was closed.
Social Security checks
A sweep of the Tacony apartment house where Weston was staying at the time of her arrest this month yielded a trove of identification records for as many as 50 people.
It included power-of-attorney paperwork, forms of identification, and Social Security numbers. Police said it suggested a vast fraud operation.
All four of the people locked in the cellar told police that Weston controlled their Social Security checks.
A big question will be whether Weston had legal control of their money as an official designee - or whether she was simply taking it.
Convicted felons are barred from being payees. The Social Security Administration "is on the red alert for people with felonies," said lawyer Richard Weishaupt of Community Legal Services.
Claims representatives for Social Security do not do background checks. A person applying for benefits on behalf of another is supposed to self-report crimes by checking a box. A 2010 audit by the Social Security Administration inspector general recommended that the agency find a cost-effective way to do background checks.
Mark Hinkle, a spokesman for the Social Security Administration, said: "We are very concerned about this situation. As this is an ongoing investigation, we can't provide you any details at this time."
Contact staff writer Jennifer Lin at 215-854-5659, firstname.lastname@example.org,
or @j_linq on Twitter.