Expert Witnesses and Scientific Evidence
Admissibility Standards
The net opinion rule, applied principally in New Jersey and comparable jurisdictions, bars expert opinion that provides a conclusion without explaining the why and wherefore. It requires the expert to give the factual bases and reasoning.
It functions similarly to the federal ipse dixit principle.
Alternative Names:
Net Opinion, Bare Conclusion Rule
Why it Matters?
The rule provides a state law route to exclusion in jurisdictions where it applies, and it operates independently of whether the state follows Daubert or Frye. Expert reports stating conclusions with a recitation of materials reviewed but no articulated reasoning are vulnerable. The rule is also applied at summary judgment, where a net opinion cannot create a genuine dispute of material fact.
Frequently Confused with
Related terms
Frequently asked questions
What does the net opinion rule require?
Does it apply at summary judgment?
