---
title: "Law Enforcement Expert Witness’ Testimony About Presence of Probable Cause Excluded"
meta:
  "og:description": "Law enforcement expert witness barred from testifying on the application and meaning of statutes and case law generally"
  "og:title": "Law Enforcement Expert Witness’ Testimony About Presence of Probable Cause Excluded"
  author: "Expert Witness Profiler"
  description: "Law enforcement expert witness barred from testifying on the application and meaning of statutes and case law generally"
---

# Law Enforcement Expert Witness’ Testimony About Presence of Probable Cause Excluded

Posted on September 20, 2024 by Expert Witness Profiler

This case arose when Defendant Jacob Salamon, a police officer for the City of Loveland, Ohio, arrested Plaintiff Amanda Caton, an off-duty police officer for the City of Cincinnati, Ohio, for operating a vehicle when intoxicated (“OVI”). Plaintiff Patrick Caton, Amanda Caton’s husband and also an off-duty police officer for the City of Cincinnati, was a passenger in the vehicle when Amanda Caton was pulled over and arrested, and he was present when Officer Salamon later dropped off Amanda Caton at their home. The Catons have sued Officer Salamon, former Loveland Police Chief Dennis Rahe, Officer Shawn Parks, and the City of Loveland for violating their civil rights.

Plaintiffs proffered [Tony Corroto](https://expertwitnessprofiler.com/expert-witness/Anthony-Corroto/1560502) and Defendants proffered  [Joseph Suhre](https://expertwitnessprofiler.com/expert-witness/Joseph-Suhre/1560501) as their experts on police practices involving OVI investigations. Plaintiffs broadly moved to exclude or limit the expert report and testimony of Suhre under  [Federal Rule of Evidence 702](https://www.law.cornell.edu/rules/fre/rule_702#:~:text=Rule%20702%20sets%20forth%20the,is%20a%20relatively%20narrow%20inquiry.) and  [_Daubert v. Merrell Dow Pharmaceuticals, Inc._, 509 U.S. 579, 113 S. Ct. 2786, 125 L. Ed. 2d 469 (1993)](https://www.law.cornell.edu/supct/html/92-102.ZS.html). Although Defendants move to strike Corroto’s expert opinion in full, they only specifically object to his opinion that Defendants lacked probable cause to stop and arrest Amanda Caton. 

## **Law Enforcement Expert Witnesses**

[Joseph Suhre](https://expertwitnessprofiler.com/expert-witness/Joseph-Suhre/1560501) is the owner and principal of Suhre & Associates DUI and Criminal Defense Lawyers. Suhre has dedicated his practice to the defense of OVI cases and other criminal offenses. Suhre has over 20 years of criminal defense experience and an additional 5 years of experience as a police officer. He has handled hundreds of DUI cases before dozens of judges in numerous counties. Because of this, Joe is uniquely qualified to defend his clients against DUI and criminal charges.

As an attorney, he completed training in OVI detection through courses with the Nation Highway Traffic Safety Administration (“NHTSA”) and Advanced Roadside Impaired Driving Enforcement, both likely more than fifteen years ago.

[Discover more cases with Joseph Suhre as an expert witness by ordering his comprehensive Expert Witness Profile report.](https://app.expertwitnessprofiler.com/login?eId=1560501)

[Tony Corroto](https://expertwitnessprofiler.com/expert-witness/Anthony-Corroto/1560502) served the City of Atlanta Police Department as a police officer for 17 years, spending 14 of them as a senior police officer assigned to the driving under the influence (DUI) task force. He specialized as a standardized field sobriety test (SFST) and drug recognition expert (DRE) instructor. He taught 46 police recruit classes DUI enforcement at the Atlanta PoliceAcademy (APA).

[Want to know more about the challenges Tony Corroto has faced? Get the full details with our Challenge Study report.](https://app.expertwitnessprofiler.com/login?eId=1560502)

## **Discussion by the Court**

## **Joseph Suhre**

Plaintiffs first argued that Suhre is not qualified to testify as a police practices expert. The Court agreed with Defendants that Plaintiffs framed the issue too broadly. The issue is whether Suhre is qualified to offer expert testimony on police practices involving investigations into potential instance of OVI by applying the NHTSA’s OVI-detection standards.

Though Suhre has not offered expert testimony in a court of law before, he has been retained to instruct about NHTSA standards by the publishing industry, attorneys, and law enforcement organizations. The Court finds that he is qualified with specialized knowledge in the application of NHTSA standards that “will help the trier of fact to understand the evidence or to determine a fact in issue.

First, Plaintiffs criticized Suhre’s statement in his expert report that Officer Salamon observed what the NHTSA refers to as a “vigilance problem” when there was “a 4-second delay between the [traffic] light turning green and Caton’s vehicle proceeding forward.” The NHTSA Visual Detection publication does not define what amount of time is “normal” versus “unusually long.” With no further guidance, the Court cannot say that Suhre’s opinion applying his own judgment to the NHTSA standard is unreliable.

Elsewhere, Suhre opines that Officer Salamon had probable cause to pull Amanda Caton over for traffic violations. However, the Court held that Suhre’s opinion that she did violate a certain traffic provision will not help a factfinder “determine a fact in issue” for purposes of Rule 702(a).

Second, Plaintiffs objected that Suhre cannot testify about whether Officer Salamon had reasonable suspicion or probable cause to pull over Amanda Caton for a violation. The Court agreed because Suhre’s opinions constituted inadmissible legal conclusions.

The Court also excluded Suhre from testifying on the application and meaning of statutes and case law generally.

#### **Tony Corroto**

Defendants do not challenge his Corroto’s qualifications to offer expert testimony. Rather, they moved to strike his testimony to the extent that he states in his report that Officer Salamon did not have probable cause to stop or arrest Amanda Caton. The Court already held in regard to Suhre’s testimony that an expert witness cannot testify about whether probable cause exists.

Therefore, the Court will strike and not consider Corroto’s report to the extent that he opines that Officer Salamon did not have probable cause to stop or arrest Amanda Caton. However, the Court refused to exclude Corroto’s report or testimony in full because of the improper opinion about probable cause.

## **Held**

The Court limited the opinions of both Joseph Suhre and Tony Corroto. Suhre will not be excluded from testifying because he is unqualified to give opinion testimony under Federal Rule of Evidence 702. Corroto will not be permitted to testify about whether probable cause existed to stop or arrest Amanda Caton, but his report will not be otherwise excluded.

## **Key Takeaways:**

- Expert witnesses may not testify to legal conclusions or to the applicability or interpretation of a particular statute or regulation. Courts are “capable” of interpreting statutes “without the assistance of an expert.

- Although an expert’s opinion may ’embrace an ultimate issue to be decided by the trier of fact, the issue embraced must be a factual one.

- Courts permit experts to testify about discrete police-practice issues when those experts are properly credentialed and their testimony assists the trier of fact.

## **Case Details:**

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