Source: http://www.vatican.va/archive/ENG1104/_P64.HTM
Timestamp: 2019-04-26 00:28:12+00:00

Document:
Can. 1574 The assistance of experts must be used whenever the prescript of a law or of the judge requires their examination and opinion based on the precepts of art or science in order to establish some fact or to discern the true nature of some matter.
Can. 1575 After having heard the parties and their suggestions, it is for the judge to appoint the experts or, if the case warrants, to accept reports already drawn up by other experts.
Can. 1576 Experts are excluded or can be objected to for the same reasons as a witness.
Can. 1577 §1. Attentive to what the litigants may bring forward, the judge is to determine in a decree the individual items upon which the services of the expert must focus.
§2. The acts of the case and other documents and aids which the expert can need to fulfill his or her function correctly and faithfully must be turned over to the expert.
§3. After having heard the expert, the judge is to determine the time within which the expert must complete the examination and produce the report.
Can. 1578 §1. Each of the experts is to prepare a report separate from the others unless the judge decrees that one report signed by the experts individually be drawn up; if this is done, differences of opinion, if there are any, are to be noted carefully.
§2. Experts must indicate clearly by what documents or other suitable means they gained certainty of the identity of the persons, things, or places, by what manner and method they proceeded in fulfilling the function entrusted to them, and above all on which arguments they based their conclusions.
§3. The judge can summon the expert to supply explanations which later seem necessary.
Can. 1579 §1. The judge is to weigh carefully not only the conclusions of the experts, even if they are in agreement, but also the other circumstances of the case.
§2. When giving reasons for the decision, the judge must express what considerations prompted him or her to accept or reject the conclusions of the experts.
Can. 1580 The judge must justly and equitably determine the expenses and fees to be paid to the experts, with due regard for particular law.
Can. 1581 §1. The parties can designate private experts whom the judge must approve.
§2. If the judge allows them, the private experts can inspect the acts of the case insofar as necessary and attend the presentation of the expert testimony; moreover, they can always present their own report.

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