(a) When a coroner has been informed that a person has been killed or suddenly died under such circumstances as to afford a reasonable ground for belief that such death has been occasioned by the act of another by unlawful means, he must forthwith make inquiry of the facts and circumstances of such death by taking the sworn statement in writing of the witnesses having personal knowledge thereof and submit the same to a judge of a court of record or a district attorney.
(b) If, upon such preliminary inquiry, the judge or district attorney is satisfied from the evidence that there is reasonable ground for believing that such death has been occasioned by the act of another by unlawful means, he must direct the coroner to forthwith summon a jury of six qualified jurors of the county to appear before him forthwith at a specified place and inquire into the cause of such death; but no person shall be liable to serve as a juror more than one time during any one year, and no person shall be paid compensation for services as a juror on more than one inquest during any one year.
(c) When five or more of the jurors appear, they must be sworn to inquire who the person was and when, where and by what means he came to his death, and to render a true verdict thereon according to the evidence offered them or arising from the inspection of the body.