Scientific claims are claims that are meant to explain the nature of reality you and I share, and scientific claims utilize the scientific method to get to the core of those claims and test if they actually do reflect reality or not. Keep in mind, the scientific method is an all encompassing and universal system. Revisions can be made if better evidence comes into play to get just that much closer to the nature of reality. It's results are consistent, repeatable, and reliable.
Courts of law are establishments utilized to settle disputes such as murder trials or law suits. Their main goal is to settle disputes as fairly as possible according to the laws of the land: to reach a fair judgement. What constitutes "fairness" is often dictated by the judge, and he will tweak the rulings as he sees fit according to those laws of the land. Keep in mind, those laws change from system to system (state to state, country to country, constitution to constitution), and valid and admittable evidence has different standards among those systems. There is no clear cut universal way to settle claims using this method.
Also, while a court case may try to reconstruct events to best reflect reality as much as possible, it can still be swayed according to the jurors, the judge, the lawyers, or the restrictions of the law (evidence can be thrown out at the whim of the judge). Keep in mind, when the times come where they do try to reconstruct events, they do utilize science to help paint that picture. DNA evidence did a LOT to set many people who were unfairly convicted free; many of these people were convicted on eye witness accounts.
Now, which spheres do you think religious claims over lap with? Claims that try to explain the nature of reality, or claims that try to settle disputes? There's a reason why Yahweh is often referred to as "god of the gaps."