A confession made by Irish teacher Ashling Murphy’s alleged killer was not influenced by any drugs given to him while in hospital, a court has heard. 

Ms Murphy, 23, was murdered while exercising on a canal path in Tullamore, Co Offaly, on January 12 last year. The killing shocked the country and led to vigils being observed across the world. 

Jurors at Dublin’s Central Criminal Court have been told father-of five Jozef Puska, 33, dragged Ashling off the walkway into some dense hedges where he stabbed her 12 times. 

One of the wounds severed her voice box, which a pathologist told them would have left her unable to scream. Witnesses said to have interrupted Puska’s attack have described seeing him hunched over the school teacher, whose legs were ‘kicking hard, like she was crying out for help’. 

Prosecutors say she died at around 3.30pm that afternoon, with her Fitbit having registered her heartrate fluctuating ‘erratically’ moments before it stopped recording one altogether. 

Last week, the court heard that Puska, who denies murder, admitted the killing while speaking to gardai in hospital via a Slovakian interpreter. 

Detective Garda Brian Jennings told the court he had questioned Puska at St James’s Hospital in Dublin on January 14. 

Relaying the translation of the interpreter, Mr Jennings said: ‘He paused and said he is making an official statement that he is admitting that he committed the murder: “I did it. I murdered. I am the murderer”.’ 

Pharmacology expert Professor Michael Ryan said the level of drugs in Puska’s system at the time would not have had an effect on his mood or behaviour. 

The defendant had been taken to hospital by ambulance on January 13. 

He told the jury he had examined the medical records of drugs administered to Puska prior to the alleged admission. 

Prof Ryan explained that he looked at what drugs were administered, what possible effects they could produce, how much was administered and what was the ‘half-life’ of the drugs. 

He said the half-life was a measure of how long the drug stays in the body and that 50% of the substance would be gone after one half life. 

Prof Ryan said Puska had undergone a laparoscopic or keyhole surgery on January 13, adding: ‘It is less severe than major surgery.’ 

The expert said Puska was given morphine but this would have been out of system by the time of the admission at approximately 6.30pm the next day. 

He said the morphine was essentially a painkiller that would have some anaesthetic use as well. 

Prof Ryan said Puska was also given the highly potent opioid fentanyl and a ‘very short-acting anaesthetic’. 

He said Puska was also given an antibiotic as part of standard procedure to prevent infection but added this would have had ‘absolutely’ no effect on mood. 

Prof Ryan said these drugs were not active in his system at the time of the alleged admission the next day. 

He said Puska was awake shortly after the surgery and the anaesthetic had worn off, with the drugs ‘completely eliminated’ well before 6pm on January 14. 

Prof Ryan said he examined the notes from Puska’s observation in the highly controlled post-operative environment. 

He said patients, their vital signs and their pain are monitored very closely in this environment. 

Prof Ryan said Puska was also given oxycodone and this was the only drug that could have had a possible influence on his mood and behaviour. 

He said it is used for post-operative pain control and the side effects are well documented and well known. 

The expert agreed with Judge Tony Hunt when asked if the drug would be ‘basically gone for all intents and purposes’ after four half-lives. 

Prof Ryan said the maximum amount of oxycodone in Puska’s system at 6pm before the alleged admission would be 8.25mg. 

He referenced a study, which was done on ‘normal volunteers’ outside a post-operative situation, that he said showed there were no effects seen in mood and behaviour on people given less than 10mg of oxycodone. 

Prof Ryan told the court that the levels of oxycodone given to Puska were ‘very much’ on the lower end of the scale. 

He also said paracetamol and ibuprofen would not have had an effect on Puska’s behaviour. 

The witness told the court there was ‘no evidence to suggest his admission was related to any drug’. 

Under cross-examination, Prof Ryan said he was not a clinical doctor and had no experience in treating patients on a ward. 

For the defence, Seoirse S O Dunlaing asked if Prof Ryan had relied on garda notes of their interactions with Puska, including that the defendant appeared distressed at one stage and an alarm had activated. 

Prof Ryan said he did not examine the detail of the garda records and that was not his expertise. 

Ms Lawlor asked the professor if he had ever heard of anyone confessing to a murder on a dosage of less than 10mg of oxycontin. 

Prof Ryan replied: ‘No.’ 

The trial continues on Wednesday. 

Get in touch with our news team by emailing us at webnews@metro.co.uk.

For more stories like this, check our news page.

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.