Law Enforcement Expert Was Allowed to Opine on the Dynamics of Sex Trafficking
Posted on November 14, 2025 by Expert Witness Profiler
Johnson is charged with three counts relating to sex trafficking or transportation of a minor for purposes of engaging in sexual activity: sex trafficking of a minor, coercion and enticement of a minor to engage in sexual activity, and interstate transportation of a minor for criminal sexual activity.
On October 3, 2025, the government notified counsel for Johnson that it intended to introduce the expert testimony of FBI Special Agent James E. Hardie who is alleged to be an expert in sex trafficking involving minors.
On October 14, 2025, Johnson filed the present motion in limine to preclude the government from introducing Hardie’s “so called ‘expert’ testimony.” He argued that Hardie’s proposed testimony is inadmissible because “it is not an area of any actual expertise,” and that “in effect, what the Government has proposed to do is elicit testimony from a law enforcement officer wherein the officer testifies that Johnson’s behavior is that of a sexual predator.”

Law Enforcement Expert Witness
James E. Hardie is a member of the FBI’s Critical Incident Response Group, National Center for the Analysis of Violent Crime, Behavioral Analysis Unit – 3. In that role, he is responsible for providing operational support to local, state, federal, and international law enforcement agencies investigating crimes against children, including sex trafficking.
Previously, Hardie served in other roles within the FBI, including supervising a squad of FBI special agents who were responsible for conducting sex trafficking investigations, working as an FBI liaison to the National Center for Missing and Exploited Children (“NCMEC”), and investigating child and adult sex trafficking cases as an FBI special agent.
Discussion by the Court
a. Scope of permissible testimony
On one hand, the government painted Hardie’s testimony as more general and described it as including: “(1) methods and techniques used in the management and procurement of commercial sex and (2) common characteristics and factors of victims of sex trafficking.” Whereas Johnson maintained that Hardie planned to testify specifically to his “expert opinion that Johnson behaved like a sexual predator.”
Having reviewed the statement of Hardie’s anticipated testimony, the Court
found that his testimony included opinions of a general nature rather than opinions specific to this case, Johnson, or Minor Victim. However, to be clear, the Court agreed with Johnson that Hardie may not testify that “ Johnson behaved like a sexual predator” or that he “must be a sexual predator.” This testimony would be tantamount to Hardie providing legal opinion and usurping the role of the jury, which is impermissible.
Again, considering Hardie’s proposed testimony as contained in the government’s notice, the Court has no reason to anticipate that Hardie will testify impermissibly.
b. Qualifications, Reliability, and Relevance
The Court found no support for Johnson’s suggestion that Hardie’s specialized knowledge is not a valid area of expertise or that his extensive experience cannot render him an expert pursuant to Rule 702.
Based on Hardie’s qualifications, and like the other courts have found with respect to Hardie’s background testimony regarding sex trafficking, the Court found that Hardie’s testimony is reliable.
The Court also found that Hardie’s testimony is relevant to the issues in this case and will be helpful to the jury. The “culture and dynamics of sex trafficking are ‘not the subject of common knowledge.’”
For these reasons, the Court made a preliminary determination that Hardie’s testimony is admissible. Furthermore, after reviewing the above-cited caselaw, the Court found that a pre-trial Daubert hearing is unnecessary.
Held
The Court denied the Defendant Johnson’s motion in limine to preclude the testimony of James Hardie.
Key Takeaway:
Hardie’s testimony will assist the jury in understanding the behaviors and dynamics of trafficking victims and traffickers as well as assist it in assessing the credibility of the witnesses.
Case Details:
| Case Caption: | USA V. Johnson |
| Docket Number: | 2:24cr221 |
| Court Name: | United States District Court, Louisiana Eastern |
| Order Date: | November 13, 2025 |





