Can a court rely on witness statements in forming their opinion?

Experts may rely on witness statements in forming their opinion. In People v. Singh, the appellant complained the expert witnesses "did not examine the cars involved or the scenes, but instead relied only upon the statements of witnesses and various reports." (People v. Singh (1995) 37 Cal.App.4th 1343, 1377.) The court found no error, explaining "[s]uch an approach is not uncommon, however, when expert witnesses become involved at trial." (Ibid.) ⁷ Because the court did not abuse its discretion in allowing the officers to testify as experts, their reliance on witness statements was not error.

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