The consequences of litigation verdicts based on uncertain scientific interpretations

https://www.cato.org/publications/commentary/roundup-usual-suspects

Why the p rule of the null hypothesis is not applied in the tort system while it is the rule in scientific papers?

First, we need to learn the practical examples of dealing with uncertainty in medicine.
Cancer
CVD
Two levels: is the null hypothesis rejected?
What is the certainty or the uncertainty of this rejection?
Is there other methods of dealing with uncertainty?