---
title: "Testimony of Rehabilitation Expert Admitted Despite Reliance on Medical Opinions"
meta:
  "og:description": "The rehabilitation expert was expected to rely upon medical opinions to estimate the quantity of medical care"
  "og:title": "Testimony of Rehabilitation Expert Admitted Despite Reliance on Medical Opinions"
  author: "Expert Witness Profiler"
  description: "The rehabilitation expert was expected to rely upon medical opinions to estimate the quantity of medical care"
---

# Testimony of Rehabilitation Expert Admitted Despite Reliance on Medical Opinions

Posted on June 4, 2025 by Expert Witness Profiler

This is a personal-injury action arising out of a motor-vehicle accident between Plaintiff Jose Ricardo Olvera-Velazquez and Defendant Jose Hernandez De La Rosa. Defendant MVT Transportation LLC (“MVT”) has stipulated that Defendant De La Rosa was acting in the course and scope of his employment with MVT at the time of the accident.

According to Plaintiff, his vehicle was struck by the 18-wheeler being driven by Defendant De La Rosa, causing severe injuries. Basically, this suit alleged claims of negligence against Defendant De La Rosa and claims against Defendant MVT for negligent hiring, retention, entrustment, supervision, and training of Defendant De La Rosa.

Plaintiff has filed motions to exclude two of the Defendants’ experts, Dr. [Mathew Greenston](https://expertwitnessprofiler.com/expert-witness/Mathew-Greenston/1540840) and Dr. [Irmo Marini](https://expertwitnessprofiler.com/expert-witness/Irmo-Marini/1512196).

## **Accident Reconstruction Expert Witness**

[Mathew Greenston](https://expertwitnessprofiler.com/expert-witness/Mathew-Greenston/1540840) is certified by the Accreditation Commission for Traffic Accident Reconstruction and is an emergency medicine physician. His education includes an undergraduate degree in mechanical engineering.

[Get the full story on challenges to Mathew Greenston’s expert opinions and testimony with an in-depth Challenge Study.](https://expertwitnessprofiler.com/order/add?eId=1540840&amp;pId=3) 

## **Rehabilitation Expert Witness**

[Irmo Marini](https://expertwitnessprofiler.com/expert-witness/Irmo-Marini/1512196) obtained his PhD in rehabilitation from Auburn University and a master’s degree in clinical psychology from Lakehead University in Thunder Bay, Ontario, Canada.

Also, he is a 2009 recipient of the National Council on Rehabilitation Education’s Distinguished Career Award in rehabilitation education, and 2010 recipient of the American Rehabilitation Counseling Association’s James F. Garrett Distinguished Career Award in rehabilitation research.

[Want to know more about the challenges Irmo Marini has faced? Get the full details with our Challenge Study report.](https://expertwitnessprofiler.com/order/add?eId=1512196&amp;pId=3)

## **Discussion by the Court**

#### **Mathew Greenston**

The Plaintiff contended that (1) Greenston’s expected testimony included an impermissible legal conclusion; (2) portions of his expected testimony did not require an expert and are not helpful to the jury; and (3) his testimony is unreliable because he did not inspect the truck at issue.

However, Plaintiff did not contend that Greenston is unqualified to testify. And Plaintiff has not identified problems with the reliability of the methodology he used either. Moreover, Defendants have satisfied their burden to demonstrate by a preponderance of the evidence that Greenston’s testimony is reliable. As a result, the Court held that the issues raised by the Plaintiff are matters more appropriately raised at trial with a motion _in limine_, through contemporaneous objection, or on cross-examination. 

#### **Irmo Marini**

To begin with, the Plaintiff argued that Marini impermissibly parrots the opinion of a medical doctor. However, the Court held that life planners like Marini must rely upon medical opinions to estimate the quantity of medical care someone will need over their lifetime. Significantly, it is undisputed that the medical doctor is expected to testify at trial to the opinions relied upon by Marini. 

Therefore, the Court decided that Greenston and Marini should not be excluded as experts, so that the District Court is able to consider specific objections to aspects of their testimony as they arise at trial and/or through any motions _in limine_.

## **Held**

In conclusion, the Court denied without prejudice the Plaintiff’s motion to exclude Defendants’ experts Mathew Greenston and Irmo Marini.

## **Key Takeaway**:

According to [Rule 703](https://www.law.cornell.edu/rules/fre/rule_703), an expert may base an opinion on facts or data in the case that the expert has been made aware of or personally observed. Thus, life planners like Marini must rely upon medical opinions to estimate the quantity of medical care someone will need over their lifetime. 

## **Case Details:**

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