Opinions and Expert Testimony

Question 1

Opinion testimony by lay witnesses

Answer 1

Lay witnesses can offer opinion testimony if rationally based on perception of witness, helpful to clear understanding or determination of a fact, VEMPS, and not stated as a legal conclusion.
o	Value of own property
o	Emotional state of others
o	Measurements
o	Physical descriptions
o	Sensory descriptions

Question 2

Testimony by experts

Answer 2

Analyze expert opinion testimony via S.P.O.T Expert Issues
o Proper Subject Matter: specialized knowledge that will help trier of fact
o Proper Person: expert has specialized knowledge
o Proper Opinion: sufficient facts or data and reliable methods
o Proper Testimony: reasonable degree of certainty

Court decides whether expert testimony comes in based on Daubert standard: TAPES
o	Tested? How extensive?
o	Acceptance in relevant community
o	Peer review
o	Error rate
o	Standard

Question 3

Bases of expert’s opinion testimony

Answer 3

Personal knowledge

Facts presented to the expert at trial

Facts presented to the expert outside of court
o Reasonable reliance rule: out of court facts must be ones reasonably relied upon by other experts in the fiel

Question 4

Opinion on an ultimate issue

Answer 4

Expert may give opinion or inference that embraces ultimate issue

In criminal cases, except as to whether a defendant is insane, experts may not give opinion as to defendant’s mental state or condition which constitutes an element of crime or defense

Question 5

Disclosing facts or data underlying expert opinion

Answer 5

Underlying data that is otherwise inadmissible cannot be revealed unless proponent shows probative value of the evidence substantially outweighs its prejudicial effect (favors exclusion)

Question 6

court-appointed experts

Answer 6

Court may appoint experts on its own or at the request of the either party
o Appointed expert must advise the parties about findings and submit to a deposition request
o May be called to testify and be cross-examined by any part