Briefly, he’s a (once respected, now not so much) statistician who was involved in exonerating the Dutch nurse Lucia de Berk who was convicted of several murders in 2001. She was subjected to an obviously unfair trial and was convicted based off of some dodgy statistics and analytical tests which genuinely couldn’t prove that she’d poisoned her patients. He then did the same for an Italian nurse who was also convicted of murdering several of her patients.
Since then he’s developed a bit of an obsession with the idea that LL is innocent and throughout the trial made dreadful accusations against other/ involved in the case, particularly Dr Jayaram and Dr Gibbs who he claimed had actually euthanized the babies. He contacted Letby’s defense and sent them a “report” containing a load of nonsense science and attempts at insulin calculations written by his scientist mate who is, in the nicest way possible, an unhinged domestic abuser. The defense told them to fuck off, so he then sent it to judge Goss, who also told them to fuck off.
At that point, Cheshire police got involved and sent the Dutch police to pay him a visit (he’s British but lives in the Netherlands), they essentially told him that unless he stopped trying to interfere with the case, he’d be held in contempt of court and arrested the next time he entered the UK, which he was not happy about at all and claimed via a soundcloud recording that it was blatant “fascism”.
Since the verdicts have come out he’s created an organization to try and get Letby freed (which includes a link for donations) and has been demanding journalists to interview him and begging people to let him onto their podcasts.
All in all, he’s basically just a massive grifter with a massive ego.