But Professor Jones says this investigation used flawed evidence – “some irrelevant, some outdated, some speculative” – adding that “newer and better evidence” is now available.

Dr Matthew Doré, honorary secretary of the Palliative Medicine Association, as well as Rachel Maskellthe Labor MP for York Central, and Chris Green, the former Conservative MP – both committee members – endorsed the professor’s interpretation of the data.

The most frequently cited finding of the select committee’s inquiry into assisted dying, published in February, is the assertion that MPs “saw no signs of deterioration in the quality or delivery of care palliative and end-of-life measures after the introduction of assisted dying; indeed, the introduction of (assisted dying) has been associated with improvements in palliative care in several jurisdictions.”

Professor Jones analyzed more recent figures and came to the opposite conclusion. It found that between 2012 and 2019, the number of palliative care services decreased by almost 5 percent in Belgium, the The Netherlands and Luxembourg, three of the four European countries where the practice is legal.

In contrast, services increased by 25 percent on average in 20 European countries where they are banned.

The anomaly was Swisswhere medical assistance in dying operates outside of traditional health care.

Belgium And Canada between 2015 and 2022, the UK also fell out of the top quartile in the global rankings for quality end-of-life care, while the UK remained in first place.

U.S. states with assisted dying also lagged behind states without assisted dying in palliative care growth between 2015 and 2019.