Why was only one man, Judge Greer, the determinant of the facts in Terri's case?
In most other cases, it is a jury that determines the facts. Certainly the facts in all capital cases are determined by a jury.
Qualified individuals can make wise judgments. An individual can also make horrific judgments. Our society has determined that groups of individuals are more likely to be wise. That is why we have city councils, company boards of directors, and jury trials. Groups of people tend to be "less imperfect" than single individuals.
Setting aside personalities, as distasteful as they appear to be, having only one person determine the facts seems to be the central failing of the judicial system in Terri's case. For the future, that failing could be solved by legislative action.
It was a civil case -- juries are for criminal cases. Of course, this was a capital case, in reality.
Probate courts don't have juries. (In Florida, guardianship matters are handled through the Probate Court, which I guess is why this matter went there.)
One impartial person with a grain of sense and a spark of humanity probably would have been fine. Unfortunately, . . .