How exactly does the law work with regards to the powers and privileges of juries. For example, in Massachusetts the law (General Laws Part III Title I Chapter 214) reads:
The supreme judicial court, upon request of a party to a civil action in which equitable relief is sought, may frame issues of fact to be tried by a jury and order the same to be tried in that court or in the superior court in the county in which such cause is pending, or upon the request of all parties in any other county.
Which gives the impression that trial is by jury and the jury has the full power over the trial. However, if we read General Laws Part III Title I Chapter 218 19B, we find something different, at least for district courts:
(c) The justice presiding over a jury of 6 session shall have and exercise all powers and duties which a justice sitting in the superior court department has and may exercise in the trial and disposition of civil cases including the power to report questions of law to the appeals court. Trials by juries of 6 shall proceed in accordance with the law applicable to trials by jury in the superior court;...
So, now all of a sudden, we have a "justice" that has some kind of power, but that power is undefined except that is the "same" as the power of a superior court justice. If we then refer to the conduct of the superior court, it reads ( General Laws Part III Title I Chapter 212 Section 2):
The court shall be held by one of the justices, and when so held shall have and exercise all the power and jurisdiction committed to said court. The chief justice shall make such assignments for the attendance of a justice at the several times and places appointed for holding the court as will be most convenient and as will insure the prompt performance of its duties.
So, here it says the court is held by the justice, not by the jury. If we then refer to the "powers" of the Superior Court, it reads in part as follows ( General Laws Part III Title I Chapter 213 Section 3: Rules; power to make and promulgate):
The courts shall, respectively, make and promulgate uniform codes of rules, consistent with law, for ...
Second, Prescribing the terms upon which amendments will be allowed or unnecessary counts and statements stricken from the record; discouraging negligence and deceit; preventing delay; securing parties from being misled; placing the party not in fault as nearly as possible in the condition in which he would have been if no mistake had been made; distinguishing between form and substance; and substituting fixed and certain requirements for the discretion of the court.
Third, Conducting trials.
Fourth, Presenting distinctly the questions to be tried by the jury.
Fifth, Giving a party such notice of the evidence which is intended to be offered by the adverse party as will prevent surprise and enable him to prepare for trial.
Sixth, Prescribing such forms of verdicts as will place upon record the finding of the jury.
So, by this Superior Court apparently can boss around the jury however it likes, so long as it is according to "rules" (not laws) which it must "promulgate".
So, my question is, if we are not dealing in law anymore but in "rules" concocted by the Superior Court:
(a) where are these "rules"? (at least in the case of Massachusetts)
(b) since the original jurisdiction seems to be vested in a "justice" not a jury, should I consider the statements concerning "trial by jury" to be just mistatements and that the jury does not have original jurisdiction in Massachusetts in any court, but that it is always the judge that has original jurisdiction?