Vaccines save lives – millions of them, in fact. If you disagree, then you can go in a specially designed box along with climate change deniers, astrologers, and flat-earthers which, when full, will be promptly launched into the sea.

Right. Now that that’s out of the way, let’s take a look at a concerning ruling that’s come out of the European Court of Justice (ECJ) recently.

A French man went to court after developing multiple sclerosis (MS), a lifelong autoimmune condition wherein your white blood cells attack a biological sheath covering your brain and spinal cord. He claimed it was because of a vaccine he received for hepatitis B. A plethora of research on the vaccine has hitherto failed to demonstrate any link with MS, but the man – known as “W” – won his case.

W received his course of inoculations between 1998 and 1999. In August of that year, W contracted symptoms of MS. Then, in 2006, his family attempted to sue the vaccine manufacturer, whom they blamed for his diagnosis.

Remarkably, at a regional court in France, W won his case. The reasoning given was that because he had no previous health issues and no family history of the illness, the vaccine must be to blame – despite there being no direct evidence of cause-and-effect.

There are multiple factors that appear to cause MS – including genetics, a lack of sunlight, heavy smoking, and associated viral infections – and in W’s case, he had not demonstrated any biological link between the vaccine and his illness.

In 2011, the Court of Appeal of Versailles overturned this decision precisely because of this lack of evidence. Remarkably, they did conclude that he had made a solid legal case that the vaccine was responsible, even if they ultimately overruled the earlier decision.

W passed away in 2011, but his family didn’t give up their fight. The case made its way through France’s highest court, who ruled that the Versailles decision should have judged the case based on W’s individual experience, not the general research and benefits of the vaccine. It then went to the Court of Appeal in Paris, who decisively concluded that W did not have a case at all, again because of the lack of scientific evidence.

This legal journey continued right up until this very year, when it made it to the highest court in the European Union, the ECJ. The legal argument given by W’s family was that, in an absence of definitive proof, circumstantial evidence be used instead if the science was shown to be inconclusive. The ECJ validated this argument, and W’s family won.

The official press release from the ECJ states that the proximity between the vaccine administration and the onset of MS, the lack of familiar history of the disease, and the existence of similar cases (coincidences and statistical anomalies, no doubt, but this was ignored) means that enough “proof” has been provided by the prosecution.

This ruling ignored scientific evidence in favor of circumstantial evidence. Essentially, the legal argument won because the ECJ mistakenly acted on the premise that the science behind the vaccine and its link to hepatitis B was unclear, even though this is not the case. Legal experts are divided on the ruling, but the scientific world is, quite understandably, aghast.

“The European Court Ruling does not appear to be consistent with the normal rational scientific approach to analysis of evidence, and the decision risks undermining vaccine programs which save millions of lives around the world every year,” Professor Andrew Pollard, Chair of the Joint Committee on Vaccination and Immunization (JCVI), said in a statement.

Let’s be clear: there’s no scientific evidence that this hepatitis B vaccine causes MS. In 2015, 887,000 people died from hepatitis B, and all of these deaths were preventable. Any efforts to undermine this vaccine aren’t just dangerous – they’re potentially deadly.

[H/T: Science]