facts in the courtroom v. facts in the laboratory

Depends how, and depends when, and depends by whom. Scientists should interpret scientific facts. But not ideologists masquerading as scientists.

And so judges should interpret the law. But not ideologists masquerading as judges.

Oh, I agree. But that is a more difficult matter. Was Souter an ideologist because he believed in a "liberal" interpretation of the law, as opposed to (say) Scalia, who is a "strict" man? There is a fuzzy area. But, of course, in principle, I agree.

I think the difference between Souter and Scalia (though I don't know enough about either to say this with any authority) is ideological at the root but this is a broad and fuzzy conception of the term 'ideology'. Is it more a difference of methodology? Is methodology rooted in ideology or vice-versa?

How do facts as understood by the scientific profession and laboratory context compare and contrast with facts as understood by the legal profession and courtroom context? There are many similarities but there must also be some major differences.