Colin Campbell Norris (born 12 February 1976) is a British serial killer who was convicted of the murder of four elderly patients and the attempted murders of two others in two hospitals in Leeds, England, in 2002.

A police investigation showed Norris to be on duty when five patients fell into sudden hypoglycaemic comas. Suspicions were raised when Norris predicted that healthy Ethel Hall would die at 5:15 am one morning, which is when she went into cardiac arrest, and tests revealed that she had been injected with an extremely high level of man-made insulin. Insulin was missing from the hospital fridge and Norris had last accessed it, only half an hour before Hall fell unconscious.

Subsequent investigations would find that the unnatural hypoglycaemic attacks followed him when he was transferred to a second hospital, and hospital records revealed that only he could not be eliminated as a suspect. Detectives believed that Norris was responsible for up to six other suspicious deaths where only he was always present, but a lack of post mortem evidence and other factors meant that investigators and the Crown Prosecution Service could not pursue convictions for these deaths.

Doubts were later raised about his conviction by, among others, Vincent Marks, an expert on insulin poisoning, who concluded from his own studies that there was a 1 in 10 chance that each patient's arrest could have happened naturally. However, others have pointed out that C-peptides are produced in hypoglycaemic attacks caused by insulin produced naturally in the body, and these were not detected in any of the blood tests of the victims, indicating that the insulin had been introduced to their bodies externally and artificially. Norris lost an appeal against his conviction in 2009. In February 2021, the Criminal Cases Review Commission referred the case back to the Court of Appeal; this second appeal, heard in 2025, was also unsuccessful.

Norris is believed to have been inspired by Jessie McTavish, a fellow Scottish nurse who was convicted of murdering a patient with insulin in 1974 before having her conviction quashed in 1975. The incident had happened at Ruchill Hospital in Glasgow, less than a mile from where Norris grew up. Shortly before he registered as a nurse, he had learned about McTavish.

Background

Norris was born and brought up in the Milton area of Glasgow, Scotland. He originally worked as a travel agent after leaving college, but after a few years in this role decided to retrain as a nurse. Friends described him as someone who loved being centre stage, and said he enjoyed amateur dramatics. His academic record was average, but he became known for being quick to anger and his aggressive confrontations with tutors and, later, employers. His behaviour towards university lecturers at the University of Dundee was described as "unacceptable". He constantly argued with his tutor, later saying that she "and I didn't exactly see eye to eye. I had a personality clash, basically 'cos I had one and she never, and she was my personal tutor." Shortly before he qualified, this tutor was known to have taught Norris about Jessie McTavish, a nurse convicted of murdering a patient with insulin at Ruchill Hospital in Glasgow, less than a mile from where Norris grew up. McTavish's conviction was overturned on appeal. Norris was then tasked with "reviewing" her conduct by the tutor. Learning about McTavish would later be regarded as a likely inspiration for Norris, and he would have believed at this point that insulin would be the "perfect" weapon for murder as it leaves the blood very quickly.

Norris began working at Leeds General Infirmary after qualifying in June 2001, but quickly fell out with experienced authority figures, finding it difficult to be told 'no' or what to do. Colleagues recounted him saying that he didn't like working on minor injury wards or with old people and wanted to work in the emergency department because it was more 'exciting' for him. He said he "wasn't put on this earth to sit in an office." The hospital later found out that he had been secretly working as a nurse in other hospitals on occasions when he claimed to be off sick or attending a training course.

His former partner said after his conviction that Norris had once hit him during an argument, bruising his head and once threw a bottle at him, which caused him to break up with Norris. He also said that, around the time of the murders, Norris had become engrossed by a storyline in Holby City, in which a serial killer nurse played by Rachel Leskovac killed patients with insulin before eventually being uncovered as a murderer. This same storyline is believed to have inspired another UK nurse, Benjamin Geen, to kill his patients. In the month in which he began killing patients with overdoses, Geen appeared in an edition of the Banbury Citizen which featured an interview with Leskovac. Norris's partner also revealed, after Norris's conviction, that Norris had experimented on his cat Casper before he began killing patients, injecting it with a lethal dose of insulin. The partner had reported him to the police but Norris claimed the cat had died from hitting its head on a wall.

Murders

Ethel Hall At the time of the murders, Norris worked at Leeds General Infirmary and St James's University Hospital in Leeds, having qualified as a nurse only a year earlier. Suspicions were raised when Norris predicted the death of one patient, Ethel Hall, saying to a fellow nurse hours before: "I predict 5:15 a.m. as being the time Ethel Hall will become unwell" since he "had a feeling about her". He said that he thought Hall was "going off tonight" and that he was a "jinx" on the hospital. This was despite there being no medical indications of an impending illness, and Hall being on the ward only for a fractured hip. Norris complained that he would have to fill out the paperwork for her death. Hall duly fell catastrophically ill that morning around 5 a.m. and she died some weeks later. When nurses including Norris came to tend to her, he tapped his watch and said to the nurse he had predicted Hall's illness earlier: "I told you". A doctor later recounted feeling "annoyed" at Norris's slow reaction to the collapse. An anonymous male nurse called Hall's son from the hospital at 5:30 a.m. that morning telling him that she had taken a "turn for the worse", and it was not established who this man was. The next night, Norris specifically called the ward to ask what had happened to Hall.

A blood sample was taken from Hall after a doctor raised concerns and ordered blood tests, and her blood was found to contain an inexplicably massive amount of insulin – 1000 units in just one sample – and this became the main hard evidence in the police case. The doctor who had ordered the tests was a diabetes expert who specialised in insulin and hypoglycaemic episodes, and she had believed the incident to be suspicious. No doctor or medical staff member had prescribed her this drug, and she had no condition that required it to be issued. The amount of insulin in Hall's blood was about 12 times the normal level, and it had been injected into her system. The insulin was manufactured and not produced naturally in the body. It had been injected into her abdomen, as indicated by the fact that a bulge was found under her skin there that was consistent with a large injection of fluid. Doctors believed it was done by someone with nursing or medical experience. The results of the tests led the hospital to contact the police.

It was discovered after Hall's death that insulin had also been taken from the storage fridge, and Norris later admitted that he was the last person to have accessed this fridge before Hall had been injected with insulin. Two vials of insulin were found to have been taken from the fridge, which had to have been taken by someone during the night shift which Norris was working when Hall became unwell. Norris had on a previous occasion been caught stealing drugs from the hospital. Norris also admitted that he was the last person to see Hall at 4.30 am, half an hour before she fell into the hypoglycaemic coma. at around 5 am.

Previous cases

Norris immediately came under suspicion and was questioned by police about Hall's murder. It was further decided to investigate the deaths of 72 people who had died on the ward while Norris was working, and a special medical panel decided that 18 of the 72 deaths should be reviewed by independent medical experts. The experts confirmed police suspicions that the deaths of three women were as a result of lethal injections of insulin, which causes hypoglycaemic attacks, but they also identified two more victims, one who had also died of insulin poisoning and another who had survived a massive injected overdose. Along with Ethel Hall, none of these women were diabetic (nor was anyone else on the ward), and all of them had been admitted to the wards simply suffering from broken hips. In any case, the amount of insulin Hall had been injected with was far in excess of what a diabetic patient would need. They were also all murdered while in non-emergency orthopaedic wards, where only minor, non-life-threatening things such as broken bones are treated. When questioned about the cases Norris said "he seemed to have been unlucky over the last 12 months."

The first three incidents occurred at Leeds General Infirmary. They began in May 2002, which also notably happened to be when the detailed probationary monitoring of Norris's early progress as a newly qualified nurse ended. On 17 May 2002, Norris injected patient Vera Wilby with an overdose of the painkiller morphine to make her drowsy (as recorded in the hospital notes and later admitted by Norris), despite the fact that she was in no pain and needed no morphine. He then administered insulin before going off shift, for no apparent medical reason. Ninety minutes after he went off shift, Wilby was found to be semi-conscious and suffering from a sudden hypoglycaemic attack, but she survived. Wilby had dementia and had been seen as a "difficult" patient by Norris. On 12 June, another patient, Doris Ludlam, was admitted to Norris's ward with a broken hip. On 25 June, she was also given an unnecessary injection of morphine (as recorded in the hospital notes and later admitted by Norris) followed by an overdose of insulin, and Norris then again went off shift. She was discovered in a coma 40 minutes after he went off shift. 88-year-old Bridget Bourke, who had been admitted to the ward on 16 June also with a broken hip, was then discovered at 3:10 a.m. on 21 July (by Norris) suffering from a hypoglycaemic attack; she died the next day.

Norris was then transferred to St James's University Hospital, and on 10 October 2002, 79-year-old Irene Crookes was admitted to Norris's new ward with a broken hip. Despite Norris recording that her condition was improving, he supposedly found her "totally unresponsive" just before 6 a.m. on 19 October, having suffered a hypoglycaemic attack. She died the next day. It was deemed significant that the bizarre cases of hypoglycaemia appeared to follow Norris when he transferred to the new especially since he was the only staff member who had been transferred. He was the only staff member who worked on both the wards in the two hospitals where all the hypoglycaemic incidents were occurring. A colleague later stated that Norris had shown no desire to revive Crookes after she fell into a coma. Another colleague also later testified that Norris had watched in "detached amusement" after one of the victims had fallen into a coma. She said that "everything he did that night had to be prompted". Significantly, it was discovered by a member of staff that they had suddenly run out of insulin after Crooke's hypoglycaemic attack.