3d Cir. Model Jury Instr. (Criminal) 2.09

The rules of evidence ordinarily do not permit witnesses to state their own

opinions about important questions in a trial, but there are exceptions to these rules.

You will hear testimony from (state the name of the person(s) who will offer an

opinion). Because of (his)(her)(their) knowledge, skill, experience, training, or

education in the field of (state the witness(es)’s field), (Mr.)(Ms.)(Dr.) (name) will be

permitted to offer (an) opinion(s) in that field and the reasons for (that)(those)

opinion(s).

The opinion(s) (this)(these) witness(es) state(s) should receive whatever weight

you think appropriate, given all the other evidence in the case. In weighing this

opinion testimony you may consider the witness' qualifications, the reasons for the

witness' opinions, and the reliability of the information supporting the witness'

opinions, as well as the other factors I will discuss in my final instructions for

weighing the testimony of witnesses. You may disregard the opinion(s) entirely if

you decide that (Mr.)(Ms.)(Dr.) (name)’s opinion(s) (is)(are) not based on sufficient

knowledge, skill, experience, training, or education. You may also disregard the

opinion(s) if you conclude that the reasons given in support of the opinion(s) are not

sound, or if you conclude that the opinion(s) (is)(are) not supported by the facts

shown by the evidence, or if you think that the opinion(s) (is)(are) outweighed by

other evidence.