A person's character, or propensity, is inadmissible to show that person's conduct on a specific occasion.

Fed. R. Evid. 703 ("unless the court determines that [the] probative value [of inadmissible facts or data] in assisting the jury to evaluate the expert's opinion substantially outweighs their prejudicial effect").Although an expert who relies on inadmissible hearsay for his or her opinion testimony should not be allowed to disclose such hearsay to the jury when giving his or her opinion testimony, the trial court should allow such hearsay to be revealed to the jury if the trial court determines that the probative value of such hearsay in assisting the jury to evaluate the expert's opinion substantially outweighs the prejudicial effect of disclosing such hearsay to the jury.

Wiener v. Farm Credit Bank of St. Louis, 759 F. Supp. 510, 521 (E.D. Ark. 1991) (holding, in plaintiff optionees' action against defendant bank for specific performance of real estate contracts, that evidence of telephone conversation....Although settlement negotiations and offers are inadmissible (i) to show the validity or invalidity of a claim when validity is in dispute, (ii) to show the amount of damages when the amount is in dispute, or (iii) to impeach by showing a prior inconsistent statement or specific contradiction, settlement evidence is admissible to show that a party had knowledge or notice of a fact.

Whittington v. Nordam Group Inc., 429 F.3d 986, 996 (10th Cir. 2005) ( Whittington v. Nordam Group Inc. 429 F.3d 986 C.A.10 (Okla.),2005. "The authorities are legion that circumstantial evidence can be every bit as compelling as direct evidence. See, e.g., Rogers v. Mo. Pac. R.R. Co., 352 U.S. 500, 508...Circumstantial evidence is not an inferior grade of evidence: it can be as strong as (or stronger than) any other kind of evidence, including eyewitness evidence, physical evidence, or scientific evidence.