Case File: Charles Cullen

Charles Cullen was born in February 1960, in West Orange, N.J., the youngest of eight children. His father died several months before he was born, leaving his mother, Florence, to raise the family with limited financial resources. Cullen later said he struggled to fit in, was frequently bullied as a child and found his greatest source of stability in his close relationship with his mother.

That stability was shattered in 1977, when Florence was killed in a car accident when Cullen was 17 years old. Friends and relatives later described her death as a devastating turning point in his life. In the years that followed, Cullen developed severe depression and began a pattern of suicide attempts and psychiatric treatment that would continue throughout adulthood.

After graduating from high school, Cullen enlisted in the U.S. Navy in 1978 and served aboard the ballistic missile submarine USS Woodrow Wilson. Although he was considered a competent sailor, his mental health continued to deteriorate, and he attempted to die by suicide during his enlistment before receiving a general discharge in 1984.

Cullen later graduated from nursing school and began working as a registered nurse at Saint Barnabas Medical Center in Livingston, N.J., in 1987. Around the same time, he married Adrienne Baum, and the couple eventually had two daughters. By the early 1990s, however, the marriage had broken down amid financial difficulties and Cullen's increasingly erratic behavior. Living alone and battling depression, he continued building a nursing career that would take him to hospitals across New Jersey and Pennsylvania.

Investigators later concluded that Cullen began killing patients in 1988 while working at Saint Barnabas Medical Center. Using his access as a registered nurse, he secretly administered lethal overdoses of medications including digoxin, insulin and other drugs. Many of his victims were elderly or critically ill, allowing their deaths to appear consistent with natural medical complications and making the murders difficult to detect.

Over the next 16 years, Cullen worked at a series of hospitals and nursing facilities throughout New Jersey and Pennsylvania, including Warren Hospital, Hunterdon Medical Center, Morristown Memorial Hospital, Liberty Nursing and Rehabilitation Center, Easton Hospital and Somerset Medical Center. At several facilities, co-workers reported unusual medication discrepancies, unexplained patient deaths or concerns about Cullen's behavior. Internal investigations were occasionally launched, but before they could be completed, Cullen typically resigned and soon found work at another hospital (though he was fired from Morristown and Liberty).

Throughout this period, Cullen's personal life remained marked by instability. He struggled with chronic depression, was hospitalized several times for psychiatric treatment following suicide attempts and continued to experience periods of emotional crisis while maintaining steady employment as a nurse. Despite these incidents, no licensing action prevented him from continuing to practice, and prospective employers often remained unaware of concerns raised at his previous workplaces.

As Cullen moved from hospital to hospital, investigators believe his victim count steadily increased. Although he later confessed to killing up to 40 patients, law enforcement officials and medical experts concluded the true number was likely much higher, because many suspicious deaths were never investigated and medical records had been destroyed or were too incomplete to prove criminal conduct years later.

By 2003, after more than a decade and a half of undetected killings, Cullen was employed in the intensive care unit at Somerset Medical Center in Somerville, N.J. It was there that a series of unexplained patient deaths finally triggered the investigation that brought his crimes to light.

The investigation that exposed Cullen began in 2003 at Somerset Medical Center, after several patients died unexpectedly from unexplained overdoses of digoxin, a medication used to treat heart conditions. Hospital officials initially suspected medication errors but grew increasingly concerned as additional patients with no medical reason to receive the drug tested positive for toxic levels.

A review of the hospital's computerized medication-dispensing system revealed a troubling pattern. Records showed Cullen repeatedly accessing medications that had not been prescribed to his patients or withdrawing drugs after patients had already died. Those findings prompted the hospital to notify the Somerset County Prosecutor's Office, which launched a criminal investigation with assistance from the New Jersey State Police.

Investigators soon consulted David Benjamin, director of the New Jersey Poison Information and Education System, whose expertise in toxicology proved critical to the case. Benjamin helped detectives interpret laboratory results and medication records, demonstrating that the overdoses were highly unlikely to have occurred accidentally. His analysis also helped identify additional suspicious deaths and strengthened the conclusion that someone had intentionally administered lethal doses of medication.

As detectives examined Cullen's employment history, they discovered a striking pattern. At nearly every hospital where he had worked, unexplained patient deaths, medication discrepancies or internal investigations had preceded his resignation. Although many of those incidents had never resulted in criminal inquiries, together they suggested Cullen had been killing patients for years while repeatedly escaping scrutiny by moving to new employers.

To obtain direct evidence, investigators enlisted the help of Amy Loughren, an intensive care nurse who had become one of Cullen's closest friends. Initially shocked by the allegations, Loughren agreed to cooperate after reviewing the evidence detectives had assembled. Wearing a concealed recording device, she met with Cullen several times while investigators monitored their conversations.

During one of those meetings, Loughren gently confronted Cullen about the suspicious deaths, urging him to tell the truth before more families suffered. Although he never directly confessed on the recordings, his responses helped corroborate investigators' suspicions and gave detectives confidence they had identified the killer.

Authorities arrested Cullen on December 12, 2003, outside a restaurant in Bridgewater, N.J. During subsequent interviews, he confessed to murdering patients at hospitals across New Jersey and Pennsylvania and agreed to help investigators identify additional victims. Detectives spent months reviewing thousands of medical records with Cullen, ultimately confirming dozens of suspicious deaths. Many other cases, however, could never be conclusively proven because records had been destroyed, victims had been cremated or too much time had passed to recover reliable forensic evidence.

Cullen was charged with multiple counts of murder and attempted murder in both New Jersey and Pennsylvania. As investigators uncovered additional victims, prosecutors in the two states coordinated their cases while continuing to review hospital records dating back more than a decade.

Facing overwhelming evidence—including medication records, toxicology reports and his own confessions—Cullen agreed to cooperate with investigators. In exchange for his continued assistance in identifying additional victims, prosecutors agreed not to seek the death penalty. Over the next several years, he accompanied investigators as they reviewed patient files from hospitals where he had worked, helping authorities identify victims whose deaths had long been considered natural or unexplained.

Between 2004 and 2006, Cullen pleaded guilty to murdering 29 patients and to multiple counts of attempted murder in New Jersey and Pennsylvania. During court proceedings, he admitted that he had intentionally administered lethal overdoses of medications including digoxin, insulin and epinephrine to patients under his care. He claimed he had acted to spare people from suffering, but prosecutors argued many of his victims were stable or recovering and had no medical reason to receive the drugs.

In March 2006, a New Jersey judge sentenced Cullen to 11 consecutive life terms, with a judge in Pennsylvania sentencing him to a 12th life term a week later. Later that year, he received six additional consecutive life sentences, again in Pennsylvania. The combined sentences ensured he would spend the remainder of his life in prison without the possibility of parole.

Following his conviction, Cullen remained incarcerated while continuing to assist investigators as they reviewed patient deaths at hospitals where he had worked. Although his cooperation helped authorities identify additional victims, many suspected murders could never be conclusively proven due to the lack of medical records, number of cremations or amount of time that had passed. As a result, many families were left without definitive answers about whether their loved ones had been among Cullen's victims.

For loved ones of those who were identified, the investigation brought a measure of closure but also renewed grief as they learned that deaths once believed to have been the result of natural causes were, in fact, homicides. Many criticized the hospitals that had employed Cullen, arguing that warning signs had been ignored and that stronger action could have prevented additional deaths. Several families filed civil lawsuits against hospitals and healthcare systems, alleging negligence and failures to protect patients.

In 2006, Cullen became the subject of another public controversy after asking to donate one of his kidneys to the relative of a friend. The request drew sharp objections from prosecutors and many victims' families, some of whom questioned whether the donation was a genuine act of compassion or an attempt to shape public perception before sentencing. A judge ultimately approved the transplant under strict conditions, and the kidney was successfully donated to the recipient.

In 2013, Cullen gave a rare interview from prison to 60 Minutes, acknowledging responsibility for the killings and again claiming he had acted to spare patients from suffering. Investigators and victims' families rejected that explanation, noting again that many of his victims were not terminally ill and had been expected to recover. Cullen remains incarcerated.

Cullen is widely regarded as one of the most prolific serial killers in modern history. Estimates have ranged from dozens of deaths to as many as 400, making his case one of the deadliest known examples of healthcare serial homicide.

The investigation also exposed significant weaknesses in how hospitals handled employees suspected of misconduct. At multiple hospitals, administrators investigated suspicious deaths, medication thefts or unusual behavior but, for the most part, allowed Cullen to resign quietly rather than terminating him for cause or notifying law enforcement. Several later provided only neutral employment references, enabling him to secure nursing positions elsewhere. Over 16 years, that pattern repeated itself as Cullen moved through at least nine healthcare facilities in New Jersey and Pennsylvania.

In response, lawmakers and healthcare regulators enacted reforms aimed at improving patient safety and communication between employers. New Jersey strengthened reporting requirements for serious preventable adverse events through its Patient Safety Act and later adopted additional measures requiring healthcare facilities to disclose when employees resigned while under investigation for conduct that could endanger patients. Similar reforms and credentialing changes were adopted elsewhere, encouraging greater information-sharing among hospitals and licensing authorities to prevent dangerous healthcare workers from quietly moving between institutions.

Cullen's crimes have been the subject of numerous books, documentaries and dramatizations. Journalist Charles Graeber's 2013 nonfiction book The Good Nurse: A True Story of Medicine, Madness and Murder chronicled both the killings and the investigation that exposed them. The book was adapted into the 2022 film The Good Nurse, starring Eddie Redmayne as Cullen and Jessica Chastain as Amy Loughren. That same year, Netflix released the documentary Capturing the Killer Nurse, featuring interviews with Loughren, investigators and others involved in the case.