First of all, a court can decide what it thinks is the truth based on testimony; but obviously, when it comes to a person’s brain, they have no absolute way of knowing if they are correct or not. However, here are links to over three dozen sworn affidavits that shed a lot more light on Terri’s condition:
http://terrisfight.org/mainlinks.php?tablesingle=main_terri_story&id=7
And here is a link to Terri’s autopsy report and related articles. (Keep in mind that thirteen days without food or hydration can and will have significant effects on all body tissue):
http://terrisfight.org/mainlinks.php?tablesingle=main_terri_story&id=2
It should also be noted the court, in 2000, examined the CAT scans at that time to reach their determination. I would imagine if those images showed anything other than her brain having been replaced by spinal fluid, the argument would have been fairly easy to prove.