Rules of Evidence of Puerto Rico CHAPTER VII OPINIONS AND EXPERT TESTIMONY Rule 701. Opinlon Testimony by Lay Witnesses If the witness is not testifying as an expert, the withess's testimony in the form of opinions and inferences is limited to those which are: (a) rationally based on the perception of the witness, (b) helpful to a clear understanding the witness's testimony or the determination of a factin issue, and {c) not based on scientific, technical, cr other specialized knowledge within the scope of Rule 702, Rule 702. Testimony by Experts If seientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue, a witness qualified as an expertpursuant to Rule 703 may testify thereto in the form of an opinion or otherwise. The probative value of the testimony shall depend, among other factors, om (a) whether the testimony is based upon sufficient facts or data, (b) whether the testimony is the product of reliable principles and methods, {c) whether the witness has reliably applied the principles and methods to the facts of the case, (d) whether the principle underlying the testimony is generally accepted by the scientific community, (e) the witness's qualifications or credentials, and () bias by the witness. The court shall rule on the admissibility of expert testimony in accordance with the factors listed in Rule 403, Rule 703, Qualification as an Expert Witness (a) A person is qualified to testify as an expert if he or she has special knowledge, skill, experience, training, or education sufficient to qualify him or her as an expert on the subject on which his or her testimony relates. Against the cbjection of a party, such special knowledge, skill, experience, training, or education must be shown before the witness may testify as an expert. (b) A witness' special knowledge, skill, experience, training, or education may be shown by any otherwise admissible evidence, including his or her own testimony. (c) A stipulation of the expert withess's qualifications does not preclude evidence a party may offer on the probative value of the expert testimony. Rule 704. Bases of Opinion Testimony by Experts The facts or data upon which an expert witness bases an opinion or inference may be those perceived or personally known by, or made known to the expert at or before the trial or hearing. If of a type reasonably relied upon by experts in the particular field in forming opinions or inferences upon the subject, the facts or data need not be admissiblein evidence. Facts or data that are otherwise inadmissible shall not be disclosed to the jury by the proponent of the opinion or inference unless the court determines that their probative value in assisting the jury to evaluate the expert's opinion substantially outweighs their prejudicial effect. Rule 705. Opinion on Ultimate Issue Testimony in the form of an opinion or inference made by an expertis not objectionable because it embraces an ultimate issue to be decided by the trier of fact. Rule 706. Disclosure of Basis of Opinion An expert may testify in terms of opinion or inference and give reasons therefor it without first testifying to the underlying facts or data, unless the court requires otherwise. The expert may in any event be required to disclose the underlying facts or data on cross-examination. Rule 707. Cross-examination of Expert Witness In addition to the provisions of Rule 607, a witness testifying as an expert may always be cross-examined as to his or her qualifications as an expert, the subject to which his or her expert testimony relates, and the basis of his or her opinion. Rule 708. Experiments () The admissibility of evidence resulting from an experiment shall be determined by the court pursuant to the provisions of Rule 403. (b) If the experiment is intended to show that certain facts occurred in a specific manner, the proponent shall persuade the court that the experiment was conducted under substantially similar circumstances as those existing at the time of the occurrence, Rule 709. Court Appointed Experts (a) Appointment The court may, on its own motion or en the motion of a party, enter an order in writing to appoint one or more court experts after affording the parties an opportunity to be heard as to the need for such appointment, submit nominatiens, and accept the appointee. The court may appoint any expert that the parties agree on and any of its own choosing. The order appointingan expert witness shall specify the expert's duties and compensation. The expert witness so appointed must notify the parties of any findings the expert makes, if any, may be deposed by any party, may be called by the court or any party, and may be cross-examined by any party, including the party that called the expert. (k) Compensation Expert witnesses so appointed are entitled to reasonable compensation in whatever sum the court may allow. In all criminal acticns or juvenile court proceedings, the compensation shall be payable from State funds. In other civil actions and proceedings, the compensation shall be paid by the parties in such proportion and at such time as the court directs, and thereafter charged like other costs. (c) Disclosure of appointment In the exercise of its discretion and after affording the parties an opportunity to be heard, the court may authorize disclosure to the jury of the fact that the court appointed the expert witness. (d) Parties' experts of own selection This Rule does not limit a party in calling its own expert