* Pursuant to 5TH CIR. R. 47.5, the court has determined

that this opinion should not be published and is not precedent

except under the limited circumstances set forth in 5TH CIR.

R. 47.5.4.

-1-

United States Court of Appeals

Fifth Circuit

FILED

October 17, 2006

Charles R. Fulbruge III

Clerk

IN THE UNITED STATES COURT OF APPEALS

FOR THE FIFTH CIRCUIT

No. 05-30555

UNITED STATES OF AMERICA

Plaintiff - Appellee

v.

OSIEL HERNANDEZ-ACUNA

Defendant - Appellant

Appeal from the United States District Court 

for the Western District of Louisiana

No. 04-50092-02

Before KING, GARWOOD, and JOLLY, Circuit Judges.

PER CURIAM*:

Defendant-appellant Osiel Hernandez-Acuna was convicted of

ten counts of transporting illegal aliens under 8 U.S.C.

§ 1324(a)(1)(A)(ii) and one count of conspiracy to transport

illegal aliens for commercial and financial gain in violation of

8 U.S.C. § 1324(a)(1)(A)(v)(I). He now appeals his conviction,

arguing that the district court erred by (1) admitting the
-2-

testimony of Agent Jon Stansel, (2) refusing to allow Professor

Robert Van Kemper to testify as an expert for the defense,

(3) denying his motion for judgment of acquittal, and (4) denying

his motion to suppress evidence. For the following reasons, we

REVERSE and REMAND.

I. FACTUAL AND PROCEDURAL BACKGROUND

Defendant-appellant Osiel Hernandez-Acuna (“Hernandez”)

worked as a relief driver for Enlaces Terrestes de Star de

Dallas, a small transportation company located in the Oak Cliff

neighborhood of Dallas, Texas. On May 16, 2004, Hernandez was

the relief driver riding in the front passenger seat of a van

when Officer Earlton Parker of the Greenwood City Police

Department stopped the driver, Jose de Jesus Contreras, for

speeding. 

Officer Parker contacted Immigration and Custom Enforcement

(“ICE”) officers. Agent Louis Patton of ICE responded to the

scene and interviewed the passengers. None of the passengers had

any valid U.S. identification such as a driver’s license, work

permit, visa, or similar documentation, but several had Mexican

identification. Agent Patton testified that he and the other ICE

agent determined that all of the passengers were illegally in the

United States. ICE took into custody all of the passengers,

except a juvenile and a pregnant woman. None of the passengers

had an alien registration number in the agency database. 
-3-

Although the passengers were initially held as material

witnesses, they were released after the government took their

depositions. 

When Hernandez was asked if he was in the United States

legally, he stated he was “in the process of becoming a

resident,” but ICE officials determined this statement to be

false. Hernandez presented a false resident-alien card to the

officers at the scene. Both Hernandez and Contreras were

arrested and charged with the transportation of illegal aliens. 

Prior to the trial, the government gave notice that it

intended to use expert testimony by Agent David O’Neal regarding

transportation regulations and Agent Jon Stansel regarding the

methods of illegal alien transportation. Hernandez and Contreras

filed a motion in limine to preclude the testimony of Agent

O’Neal and Agent Stansel as expert witnesses. The district court

granted the motion in part and denied it in part. The court

permitted O’Neal and Stansel to testify as experts, but it

ordered that the experts could not give testimony that would

violate Rule 704(b). 

The district court denied the motion to suppress evidence

obtained during the traffic stop. Hernandez filed a motion to

reconsider, arguing that Officer Parker observed the traffic

violation while outside his jurisdiction, and the district court

denied it as well. 

When Contreras did not appear for trial, the district court
-4-

severed the case and tried Hernandez individually. Over an

objection by Hernandez, the government’s case-in-chief included

testimony by Agent Stansel regarding the methods of illegal alien

transportation. To rebut Agent Stansel’s testimony, Hernandez

offered Professor Robert Van Kemper as an expert in cultural

anthropology. Van Kemper was to testify regarding the use of

camioneta vans by Hispanics in both Mexico and the Dallas area. 

The district court excluded Van Kemper’s testimony pursuant to

Rule 704(b) and for the further reason that it was not, in the

court’s view, sufficiently reliable, and Hernandez objected to

that ruling.

At the conclusion of the government’s case-in-chief,

Hernandez moved for a judgment of acquittal which was denied. 

After a three day trial, a jury found Hernandez guilty of all

eleven counts. The district court sentenced Hernandez to

eighteen months imprisonment for each count, with the sentences

to be served concurrently. Hernandez timely appealed. 

II. EXPERT TESTIMONY

A. Standard of Review

A district court’s decision to admit or exclude evidence is

reviewed for abuse of discretion. United States v. GutierrezFarias, 294 F.3d 657, 662 (5th Cir. 2002). Any error in

admitting evidence is subject to harmless error review. United

States v. Williams, 957 F.2d 1238, 1242 (5th Cir. 1992).
-5-

B. Agent Stansel’s Testimony

Hernandez was charged with transportation of illegal aliens

in violation of 8 U.S.C. § 1324(a)(1)(A)(ii), which prohibits

transporting illegal aliens knowing or with a reckless disregard

for their immigration status. Hernandez’s challenge to Agent

Stansel’s testimony revolves around whether Hernandez knew about

or recklessly disregarded the passengers’ illegal status. Agent

Stansel, a senior special agent with ICE, testified as an expert

for the government. Hernandez argues that the district court

erred when it admitted the testimony of Agent Stansel because

certain portions of his testimony on Hernandez’s mental state

came “unacceptably close” to illegal profiling.

The Federal Rules of Evidence set out when a district court

may permit expert testimony on a matter in dispute at trial. If

scientific, technical, or specialized knowledge will aid the

trier of fact in understanding the evidence or determining a fact

in issue, an expert may testify. FED. R. EVID. 702. The expert,

however, must be qualified by knowledge, skill, experience,

training, or education. Id. The testimony must be based “upon

sufficient facts or data . . . [and] the product of reliable

principles and methods.” Id. Critically for our purposes, an

expert in a criminal case may not offer “an opinion or inference

as to whether the defendant did or did not have the mental state

or condition constituting an element of the crime charged.” FED.
1 The parties do not address the required mental state

for Hernandez’s conspiracy conviction. At the district court,

the jury instruction for the conspiracy count read: “United

States Code, Section 1324(a)(1)(A)(I) makes it a crime for anyone

to conspire with someone else to transport or attempt to

transport an illegal alien within the United States, knowing or

in reckless disregard of the fact that the illegal alien is here

illegally, and in furtherance of the illegal alien’s violation of

the law.” Neither party objected to the jury instructions. 

Agent Stansel’s improperly admitted testimony also affects the

conspiracy conviction because the mental state in the jury

instruction for conspiracy is the same as the mental state for

the transportation of illegal aliens.

-6-

R. EVID. 704(b). The defendant’s mental state is an issue for

the trier of fact alone. Id.

The district court erred in allowing Agent Stansel to

testify to Hernandez’s mental state.1 A fine “borderline” exists

between an improper opinion regarding the defendant’s mental

state and “a mere explanation of the expert’s analysis of facts”

relating to the defendant’s mental state. See United States v.

Speer, 30 F.3d 605, 610 (5th Cir. 1994). An expert witness may

violate Rule 704(b) by either explicitly offering an opinion as

to the defendant’s state of mind or by giving the functional

equivalent of such a statement. Id.; Gutierrez-Farias, 294 F.3d

at 663. 

In Gutierrez-Farias, a Drug Enforcement Agency (“DEA”) agent

testified as an expert on the business of transporting narcotics

through South Texas, and we held that admission of that expert

testimony was an abuse of discretion. See 294 F.3d at 663. The

DEA agent’s testimony suggested that, because most drivers know
-7-

when they are smuggling drugs in their vehicles, Gutierrez must

have known he was smuggling drugs. Id. “Rather than assisting

the jury to understand the evidence presented on complicated fact

issues, the agent presented the jury with a generalization that

in most drug cases the person hired to transport the drugs knows

that the drugs are in the vehicle.” Id. We held that this

generalization was the functional equivalent of an agent’s direct

comment on the defendant’s mental state and thus violated Rule

704(b). Id.

In United States v. Mendoza-Medina, we held that the

admission of similar expert testimony was an abuse of discretion.

346 F.3d 121, 128 (5th Cir. 2003). In Mendoza-Medina, a DEA

agent testified about how people are recruited to transport

drugs, the correlation between the amount of drugs in a load and

the experience of the transporter, the importance of trust

between the distributor and driver, and the practice of narcotic

traffickers bringing their wives and children along with the

specific intent of masking the drug trafficking offense. 346

F.3d at 127-28. Because Mendoza-Medina had his wife and child

with him at the time of the stop, these generalized comments

about distributors having to trust their couriers and the

couriers’ practice of bring their families along were

effectively used as substantive evidence that Mendoza-Medina also

knew he carried drugs. Id. We held that use of this testimony

was a violation of Rule 704(b) and came “unacceptably close” to
-8-

illegal profiling. See id. at 125. 

In this case, Agent Stansel testified that “camioneta” is a

Spanish word meaning small bus or van and that law-enforcement

officials generally refer to a camioneta operation as a van

company that does not comply with regulations and that transports

illegal aliens across the United States. He also noted that

smugglers bring illegal aliens directly to the van companies,

which then transport the aliens from larger cities, such as

Houston and Dallas, to other locations in the United States. 

According to Agent Stansel, camioneta operations are considered a

“front” for alien smuggling operations and do not put signs on

their vans to avoid detection. The camioneta passengers do not

volunteer that they are illegal aliens, and the company does not

ask questions regarding the passengers’ immigration status so

that its personnel can say they were unaware of it. Agent

Stansel testified: 

Q. Now, Mr. Gilley was talking to you about,

you know, what was required as far as asking

for identification or verifying alien status.

A. That’s correct.

Q. Based on your understanding of those

requirements, can someone just simply turn a

blind eye to evidence that would indicate such

and just plead ignorance? 

A. No, sir. Then they would be recklessly

disregarding the fact that those people might

be illegally in the country. 

Q. And again, these are not the kind of

operations where someone’s going to ask or
-9-

someone’s going to tell, right?

A. That’s correct. 

Q. And why is it that this is the practice?

A. It is so that in a situation such as we have

today, if you’re - - 

Q. Well, wait. Let’s talk about your

experience. 

A. Right. In my experience, if they’re

apprehended, then they can say: ‘I didn’t know,

I didn’t talk to any of the people and I didn’t

know what their immigration status was.’

In Agent Stansel’s opinion, border patrol agents watch for

camioneta vans because they are “100% illegal” and the facts of

this case were consistent with camioneta operations that he had

investigated in the past. 

Agent Stansel’s generalization about the typical camioneta

operation--that when the drivers avoid asking for or receiving

information from aliens about their immigration status, they

recklessly disregard the fact that their passengers may be in the

country illegally--is problematic. His testimony is similar to

the generalizations regarding the typical drug-smuggling

operations in Mendoza-Medina and Gutierrez-Farias. GutierrezFarias, 294 F.3d at 663; Mendoza-Medina, 346 F.3d at 127-28. 

Although Agent Stansel did not expressly say that Hernandez knew

or recklessly disregarded his passengers’ illegal immigration

status, the clear inference was that Hernandez did so because the

facts in this case were consistent with the typical camioneta
2 The government urges us to follow two unpublished

opinions from the Ninth Circuit that permit expert testimony in

transportation-of-illegal-alien cases. See United States v.

Salazar-Munoz, 242 F.3d 385, 2000 WL 1529233 (9th Cir. 2000)

(unpublished table decision); United States v. Vaca-Hernandez,

185 F.3d 871, 1999 WL 451214 (9th Cir. 1999) (unpublished table

decision). Those cases are different from the situation in this

case because while the expert testimony was admitted, the agents’

comments did not go to the defendants’ intent, knowledge, or

mental state. See id.

-10-

operation where, according to Agent Stansel, immigration status

is disregarded. This is the “functional equivalent” of an

express comment on Hernandez’s mental state. See GutierrezFarias, 294 F.3d at 663. The district court’s admission of this

testimony by Agent Stansel was therefore an abuse of discretion.2

We do not hold that all of Agent Stansel’s testimony was

improperly admitted; only that which amounted to a comment on

Hernandez’s mental state was improper. If expert testimony would

be helpful in assisting the trier of fact in understanding the

evidence, background testimony by an expert familiar with the

methods of transporting and smuggling illegal aliens is

permitted, so long as the testimony does not comment on the

defendant’s mental state. See United States v. Washington, 44

F.3d 1271, 1283 (5th Cir. 1995)(holding that an experienced

narcotics agent may testify about the significance of certain

conduct or methods of operation unique to the drug distribution

evidence). 

We must next decide whether the error was harmless. Even

when expert testimony is erroneously admitted, reversal is not
-11-

required if the error is harmless. Gutierrez-Farias, 294 F.3d at

663. “[U]nless there is a reasonable possibility that the

improperly admitted evidence contributed to the conviction,

reversal is not required.” Mendoza-Medina, 346 F.3d at 127

(citing Williams, 957 F.2d at 1242). 

In both Mendoza-Medina and Gutierrez-Farias, the error was

found to be harmless due to the substantial additional evidence

provided at trial. Gutierrez-Farias, 294 F.3d at 663; MendozaMedina, 346 F.3d at 127-28. For example, in Mendoza-Medina the

defendant had confessed to smuggling drugs and the confession was

corroborated by other evidence. 346 F.3d at 129. In GutierrezFarias, the agent’s improper testimony was only a small part of

“an otherwise strong case.” 294 F.3d at 663. Further, the

district court attempted to cure the defects in the agent’s

testimony by instructing the jury that it could not rely on the

agent’s testimony alone as proof of the defendant’s mental state. 

Id.

In this case, however, the circumstantial evidence is not

nearly as strong as that in Gutierrez-Farias and Mendoza-Medina. 

See Gutierrez-Farias, 294 F.3d at 663; Mendoza-Medina, 346 F.3d

at 127-28. There is no direct evidence of Hernandez’s knowledge,

and apart from Agent Stansel’s testimony, the evidence of

Hernandez’s knowledge of the passengers’ immigration status is

slim. Hernandez did not confess to the crime charged, act

aggressively toward law enforcement, or appear nervous during the
-12-

stop. Agent Stansel’s testimony served as a crucial part of the

evidence presented at trial and provided the “link” that

established Enlaces’s operations as similar to the typical

illegal camioneta operation. The error in admitting Agent

Stansel’s testimony is harmful because there is more than a

“reasonable possibility that the improperly admitted evidence

contributed to the conviction.” Mendoza-Medina, 346 F.3d at 127. 

C. Professor Van Kemper’s Testimony

Hernandez argues that the district court abused its

discretion in refusing to admit the testimony of his expert

witness, Robert Van Kemper, Professor of Cultural Anthropology at

Southern Methodist University. 

Hernandez contends that because the evidence of Professor

Van Kemper was relevant and necessary to counter Agent Stansel’s

testimony, it should have been admitted. The district court’s

ruling was based on what the court perceived to be a problem with

the reliability of Professor Van Kemper’s testimony, as well as a

problem with Rule 704(b). The district court may exclude expert

testimony if the underlying basis for the expert’s opinion is not

sufficiently reliable. See Daubert v. Merrell Dow Pharm., Inc.,

509 U.S. 579, 589 (1993); FED. R. EVID. 702. One of the factors

the district court is to consider when assessing whether the

methodology is scientifically valid or reliable is whether the

theory has been subject to peer review and publication. Moore v.
-13-

Ashland Chem. Inc., 151 F.3d 269, 275 (5th Cir. 1998). Professor

Van Kemper’s testimony relied largely upon one study on

camionetas done by a professor in Los Angeles, and the district

court expressed doubt as to the reliability of that study because

it was not peer reviewed. The court did not abuse its discretion

by excluding Professor Van Kemper’s testimony as not sufficiently

reliable.

With respect to Rule 704(b), the court concluded that

Professor Van Kemper was qualified as an anthropologist, but

found that Rule 704(b) prohibited his testimony and noted that

Professor Van Kemper was in no better position than a juror to

conclude whether Hernandez’s actions demonstrated knowledge or

reckless disregard of the passengers’ immigration status. 

Because the purpose of Professor Van Kemper’s testimony was to

negate Agent Stansel’s testimony and to provide other evidence

concerning Hernandez’s state of mind, the testimony was

rightfully excluded under Rule 704(b). Gutierrez-Farias, 294

F.3d at 663; Mendoza-Medina, 346 F.3d at 127-28. 

III. SUFFICIENCY OF THE EVIDENCE

A. Standard of Review

We review a challenge to the sufficiency of the evidence in

the light most favorable to the government. United States v.

Burton, 324 F.3d 768, 770 (5th Cir. 2003). Hernandez made a Rule

29 motion for judgment of acquittal at the close of the
-14-

government’s case-in-chief, but because he failed to renew his

motion at the close of the evidence, we review his claim to

determine “whether there was a manifest miscarriage of justice.” 

Id. (quoting United States v. Galvan, 949 F.2d 777, 783 (5th Cir.

1991)). A manifest miscarriage of justice “occurs only where

‘the record is devoid of evidence pointing to guilt or contains

evidence on a key element of the offense [that is] so tenuous

that a conviction would be shocking.’” United States v. McIntosh,

280 F.3d 479, 483 (5th Cir. 2002) (quoting United States v.

Cathey, 259 F.3d 365, 368 (5th Cir. 2001) (internal citations

omitted) (alteration in original)). We review the sufficiency of

the government’s case in light of all the evidence, including the

disputed expert testimony. See e.g., United States v. Marshall,

762 F.2d 419, 423 (5th Cir. 1985) (holding defendant not entitled

to have the court of appeals disregard inadmissible evidence in

conducting sufficiency of evidence review). 

B. Analysis

To convict Hernandez of transporting illegal aliens, the

jury had to find beyond a reasonable doubt that (1) an alien

entered or remained in the United States in violation of the law,

(2) Hernandez transported the alien within the United States with

intent to further the alien’s unlawful presence, and

(3) Hernandez knew or recklessly disregarded the fact that the

alien was in the country in violation of the law. 8 U.S.C.
3 Hernandez’s brief does not address the sufficiency of

the evidence with regard to an element of the conspiracy

conviction under 8 U.S.C. 1324(a)(1)(A)(v)(I). Therefore, we do

not discuss the sufficiency of the evidence as to the conspiracy

conviction because inadequately briefed issues are deemed

abandoned. Dardar v. LaFourche Realty Co., 985 F.2d 824, 831

(5th Cir. 1993) (citing Friou v. Phillips Petroleum Co., 948 F.2d

972, 974 (5th Cir. 1991). 

-15-

§ 1324(a)(1)(A)(ii); United States v. Nolasco-Rosas, 286 F.3d

762, 765 (5th Cir. 2002). Because circumstantial evidence is

sufficient to establish knowledge of alien status, direct proof

of Hernandez’s state of mind is unnecessary. United States v. De

Jesus-Batres, 410 F.3d 154, 161 (5th Cir. 2006); United States v.

Romero-Cruz, 201 F.3d 374, 379 (5th Cir. 2000). 

Hernandez argues that the government failed to introduce

sufficient evidence to show he knew or recklessly disregarded

that the passengers were illegal aliens.3 Hernandez contends

without Agent Stansel’s testimony the jury could not find that

Hernandez recklessly disregarded that his passengers were illegal

aliens. But, Hernandez is not entitled to have Agent Stansel’s

testimony excluded from the sufficiency of the evidence review,

see Marshall, 762 F.2d at 423, and with Agent Stansel’s

testimony, the evidence is more than sufficient to sustain the

conviction. 

Even if, for the sake of argument we exclude Agent Stansel’s

testimony bearing directly on Hernandez’s state of mind, the

record is not devoid of evidence pointing to Hernandez’s guilt,

nor is the evidence so tenuous that a conviction would be
-16-

shocking. The remainder of Agent Stansel’s testimony, in

addition to Officer Parker’s and Agent Patton’s testimony

describing the condition of the van’s passengers, suggests that

Hernandez may have recklessly disregarded the passengers’ illegal

status. For instance, the evidence showed: (1) that the

passengers had utilized a small transport company operated by and

for Spanish-speaking individuals; (2) that the van company

allowed payment at the destination rather than requiring payment

up front; (3) that all the passengers appeared to be Hispanic;

(4) that there was a “strong odor” indicating that some of the

passengers had not bathed recently; (5) that the van was crowded;

(6) that the passengers’ clothing was “dingy”; (7) that they had

little luggage in the van, a mere four or five backpacks among

twelve passengers each taking a long distance trip; (8) that

safety equipment was not in the van; and (9) that the exterior of

the van was unmarked. 

In sum, Hernandez has not demonstrated that a manifest

miscarriage of justice has occurred or that the record is so

devoid of evidence that Hernandez recklessly disregarded the

passengers’ status as to make his conviction shocking. See

Burton, 324 F.3d at 770-71; Nolasco-Rosas, 286 F.3d at 765-66. 

IV. MOTION TO SUPPRESS

A. Standard of Review
-17-

We review the district court’s factual findings on a motion

to suppress for clear error, and we review de novo its legal

findings, including its ultimate conclusion as to the

constitutionality of the law enforcement action. United States

v. Carreon-Palacio, 267 F.3d 381, 387 (5th Cir. 2001). We view

the evidence in the light most favorable to the party that

prevailed in the district court. United States v. Jordan, 232

F.3d 447, 448 (5th Cir. 2000). 

B. Analysis

Hernandez argues that the district court erred in denying

his motion to suppress. He contends that Officer Parker exceeded

his jurisdiction under state law because the van was not within

Officer Parker’s jurisdiction when the van was clocked at eightyone miles per hour in a seventy mile-per-hour zone. 

Hernandez recognizes that this issue is controlled by our

decision in United States v. Garcia, 719 F.2d 108 (5th Cir.

1983), but he asserts that Garcia was erroneously decided. 

Hernandez asks the court to reassess its prior rulings in Garcia,

and United States v. Jones, 185 F.3d 459 (5th Cir. 1999). We

decline to revisit our holdings in Garcia and Jones. The

decisions of prior panels are binding on this court. United

States v. Martin, 431 F.3d 846, 853 (5th Cir. 2005). 

When evidence secured by a state official is used against a

defendant accused of a federal offense, the pertinent question is
-18-

whether the state official violated the Fourth Amendment in

securing the evidence. Issues regarding local law-enforcement

jurisdiction do not govern in a federal criminal action. United

States v. Walker, 960 F.2d 409, 415 (5th Cir. 1992). The

district court, therefore, properly denied Hernandez’s motion to

suppress. 

V. CONCLUSION

For the foregoing reasons, we REVERSE Hernandez’s

convictions and REMAND to the district court.