It would help if the legal profession (at least in the US) did not actively select against numeracy. The running joke in law school is that everyone who was a decent student but bad at math goes to law school because the LSATs do not have a math component, unlike the GREs. I’m an engineer and former lawyer, and when I was in law school I actually ended up taking a really disproportionate number of tax law classes because I was so much better than my average peer at basic arithmetic that I could always beat the curve in classes that required basic calculations. And we’re not talking about even intro level algebra, just basic arithmetic. Addition, subtraction, some multiplication and division.
By ignoring math skills altogether, the legal profession necessarily ends up selecting for individuals who on average have a poorer understanding of anything quantitative or statistical, and often that also correlates with poorer understanding of all technical and scientific matters, because the same innumeracy means those individuals don’t make it far any sciences at all, even in their secondary or tertiary education. So they often don’t even have strong fundamentals on the basic concepts in those areas.
As an engineer, it was maddening to witness and absolutely pervades every aspect of the US legal system. Which both translates into reaching false factual conclusions as in OP, but also infects legal reasoning with a ridiculous lack of rigor (a point which lawyers often dispute vigorously, but they have no concept of just how much rigor they lose by eschewing mathematical and especially statistical reasoning), and it also translates into poorer operational efficiency and administrative efficiency in the legal system, and poorer outcomes from the regulatory system, which, while often informed by technical concerns, remains a primarily legal- and lawyer- driven process. That opens up regulatory bodies to subjective political concerns where there is absolutely no reasonable technical case to be made. This phenomenon is most obvious in recent history with climate change related regulations, but is pervasive throughout the US policy making establishment, and contributes substantially to our challenges with special interests and regulatory capture.