§ 90.705, Fla. Stat. — Disclosure of Facts or Data Underlying Expert Opinion
Plain English
This rule lets an expert get to the point. Unless the court requires otherwise, an expert can state the opinion and reasons first, without laying out all the underlying facts or data up front — and the burden shifts to cross-examination, where the expert must then specify those facts or data. Florida adds a sharp tool in subsection (2): before the expert gives the opinion, the opposing party may conduct a voir dire on the underlying basis. If that party makes a prima facie showing the expert lacks a sufficient basis, the opinion is inadmissible unless the proponent establishes the underlying facts or data.
From the Courtroom
90.705(2) is an underused weapon. Before the expert ever delivers the headline opinion, you can take them on voir dire and try to show the foundation is hollow. Make that prima facie showing and the burden flips to the other side to prop up the basis — a moment that can quietly gut an opinion before the jury ever leans on it.
Key Points & Authority
- § 90.705(1), Fla. Stat. — An expert may give an opinion and reasons without prior disclosure of the underlying facts/data; on cross-examination the expert must specify them.
- § 90.705(2): the opponent may voir dire on the basis before the opinion is given; a prima facie showing of insufficient basis renders the opinion inadmissible unless the proponent establishes the underlying facts.
- Federal parallel: Fed. R. Evid. 705 (same number) allows opinions without prior disclosure, with disclosure compelled on cross.
Federal Parallel
The federal counterpart is Fed. R. Evid. 705 — same numbering and the same core: an expert may state an opinion without first disclosing the underlying facts, which can be drawn out on cross-examination (the federal rule does not spell out Florida’s pre-opinion voir-dire mechanism).
About this rule walkthrough
Part of The Evidence Code, hosted by John M. Phillips — Board Certified Civil Trial Lawyer, Court TV analyst, admitted in 8 states + 9 federal districts + SCOTUS.
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Educational only — not legal advice.
Rule Text (verbatim from the Florida Supreme Court)
(1) Unless otherwise required by the court, an expert may testify in terms of opinion or inferences and give reasons without prior disclosure of the underlying facts or data. On cross-examination the expert shall be required to specify the facts or data.
(2) Prior to the witness giving the opinion, a party against whom the opinion or inference is offered may conduct a voir dire examination of the witness directed to the underlying facts or data for the witness’s opinion. If the party establishes prima facie evidence that the expert does not have a sufficient basis for the opinion, the opinions and inferences of the expert are inadmissible unless the party offering the testimony establishes the underlying facts or data.
Educational reference. Educational only — not legal advice.
What this rule means in plain English
Section 90.705 allows an expert to give an opinion without prior disclosure of underlying facts/data (specified on cross), and lets the opponent voir dire on the basis before the opinion — a prima facie showing of insufficient basis renders the opinion inadmissible unless the proponent establishes the facts.