1:1-15.9 Expert and other opinion testimony
(a) If a witness is not testifying as an expert, testimony of that witness in the form of opinions or inferences is limited to such opinions or inferences as the judge finds:
1. May be rationally based on the perception of the witness; and
2. Are helpful to a clear understanding of the witness testimony or to the fact in issue.
(b) If a witness is testifying as an expert, testimony of that witness in the form of opinions or inferences is admissible if such testimony will assist the judge to understand the evidence or determine a fact in issue and the judge finds the opinions or inferences are:
1. Based on facts and data perceived by or made known to the witness at or before the hearing; and
2. Within the scope of the special knowledge, skill, experience or training possessed by the witness.
(c) Testimony in the form of opinion or inferences which is otherwise admissible is not objectionable because it embraces the ultimate issue or issues to be decided by the judge.
(d) A witness may be required, before testifying in terms of opinions or inference, to be first examined concerning the data upon which the opinion or inference is based.
(e) Questions calling for the opinion of an expert witness need not be hypothetical in form unless, in the discretion of the judge, such form is required.
(f) If facts and data are of a type reasonably relied upon by experts in the particular field in forming opinions or inferences upon the subject, those facts and data upon which an expert witness bases opinion testimony need not be admissible in evidence.
N.J.A.C. 1:1-15.10 (2016)