PRECEDENTIAL

UNITED STATES COURT OF APPEALS

FOR THE THIRD CIRCUIT

_______________

No. 11-1733

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UNITED STATES OF AMERICA

v.

KEENAN DANAN QUINN,

Appellant

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On Appeal from the United States District Court

For the Eastern District of Pennsylvania

(D.C. Criminal Action No. 2-09-cr-00720-002)

District Judge: Honorable Petrese B. Tucker

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Argued En Banc February 20, 2013

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Before: McKEE, Chief Judge, SLOVITER, SCIRICA,

RENDELL, AMBRO, FUENTES, SMITH, FISHER, 

CHAGARES, JORDAN, HARDIMAN, 

GREENAWAY, Jr., VANASKIE, and 

ALDISERT, Circuit Judges
2

(Opinion filed: August 14, 2013 )

Peter Goldberger, Esquire (Argued)

Pamela A. Wilk, Esquire

50 Rittenhouse Place

Ardmore, PA 19003

Edward C. Meehan, Jr., Esquire

Edward C. Meehan, Jr. & Associates

211 North 13th Street, Suite 701

Philadelphia, PA 19107

Counsel for Appellant

Zane David Memeger, Esquire

United States Attorney

Robert A. Zauzmer, Esquire (Argued)

Assistant United States Attorney

David L. Axelrod, Esquire

Assistant United States Attorney

Office of United States Attorney

615 Chestnut Street, Suite 1250

Philadelphia, PA 19106

Counsel for Appellee

Ellen C. Brotman, Esquire

Erin C. Dougherty, Esquire

Montgomery, McCracken, Walker & Rhoads

123 South Broad Street, 28th Floor

Philadelphia, PA 19109
3

Jenny Carroll, Esquire 

Seton Hall University School of Law

One Newark Center

Newark, NJ 07102

Amicus Curiae Counsel

National Association of Criminal Defense Lawyers

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OPINION OF THE COURT

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AMBRO, Circuit Judge, with whom McKEE, Chief Judge, 

SLOVITER, SCIRICA, RENDELL, FUENTES, SMITH, 

FISHER, CHAGARES, JORDAN, HARDIMAN, 

GREENAWAY, Jr., VANASKIE, and ALDISERT, Circuit 

Judges, join.

Keenan Quinn appeals his jury conviction for aiding 

and abetting codefendant Shawn Johnson in an armed bank 

robbery. Quinn’s defense was that, when he drove Johnson to 

National Penn Bank on the morning of the robbery, he did not 

know that Johnson intended to rob a bank teller at gunpoint.

Quinn hoped Johnson would testify on his behalf at trial, but 

Johnson—who was awaiting sentencing on the robbery 

charges—invoked his Fifth Amendment protection against 

self-incrimination and refused to testify. The District Court’s 

refusal of Quinn’s request to immunize Johnson so he could 

testify was, Quinn contends, an error, for without it he was 

unable to rebut the Government’s accusations against him. 

Quinn also alleges (though belatedly) prosecutorial 

misconduct. Specifically, he asserts that the Government 
4

postponed Johnson’s sentencing until after Quinn’s trial to 

induce Johnson to invoke his Fifth Amendment privilege.

We have recognized two situations in which a criminal 

defendant may be entitled to have a defense witness receive

immunity for his testimony. The first, grounded in 

prosecutorial misconduct, occurs when the Government acts

“with the deliberate intention of distorting the judicial fact

finding process” (for example, by threatening a defense

witness). United States v. Herman, 589 F.2d 1191, 1204 (3d 

Cir. 1978); United States v. Morrison, 535 F.2d 223 (3d Cir. 

1976). If prosecutorial misconduct occurs, the charges are 

dismissed unless the Government chooses to immunize the 

witness at a new trial.

We recognized a second situation in Government of 

the Virgin Islands v. Smith, 615 F.2d 964 (3d Cir. 1980)—

even without evidence of prosecutorial misconduct, if the 

Government has refused to immunize the witness, the 

defendant is entitled to immunity for his witness if the 

testimonial evidence is “clearly exculpatory and essential to 

the defense case and . . . the government has no strong 

interest in withholding use immunity.” Id. at 974. If those 

requirements (detailed in a five-part test) are met, the District 

Court, as a new remedy accorded by Smith, may on its own 

authority immunize that witness to allow his testimony. Id. at 

971–72. 

No statute or Supreme Court ruling authorizes judicial 

grants of immunity for a defense witness (called for 

convenience judicial use immunity). We are the only Court 

of Appeals that permits a trial court to immunize a defense 

witness. Every other Court of Appeals has rejected this 
5

theory of judicial power. Today we do so as well, and 

overturn that part of Smith that recognizes judicial grants of 

immunity. Immunity is a statutory creation, bestowed by 

Congress on the Executive Branch through the federal 

witness immunity statute, 18 U.S.C. §§ 6002, 6003. The 

decision to immunize a witness to obtain his testimony is a

core prosecutorial function, as immunizing necessarily 

involves weighing the public’s need for testimony against the 

risk that immunity will inhibit later prosecution of criminal 

wrongdoing. We, in our corner of the Judiciary, now step 

away from our reach into this prosecutorial realm.

Though we abandon the judicial use immunity remedy

created in Smith, we retain its five-part test for determining 

whether the Government’s refusal to grant defense witness 

immunity denies a defendant due process. We created this 

test in Smith because we feared our then-existing test for 

prosecutorial misconduct—acts taken with an intent to distort 

the factfinding process—did not ensure the defendant’s right 

to present an effective and meaningful defense when the 

prosecutor refused to immunize a witness. Smith asks 

whether the Government has refused to immunize a witness 

in order to keep clearly exculpatory and essential testimony 

from trial without a strong countervailing reason. If so, this is 

a type of prosecutorial misconduct. The Smith test thus 

complements our existing prosecutorial misconduct test. 

However, the remedy for a due process violation, rather than 

intruding into the prosecutor’s province by judicial grants of 

immunity, is a retrial where the Government can cure the 

distortion caused by its wrongdoing or face dismissal of the 

relevant charges. 
6

Applying both the prosecutorial misconduct test that 

existed before and after Smith (acts taken with the deliberate 

intent to distort the factfinding process) and the 

complementary test we created in Smith (exclusion of clearly 

exculpatory and essential testimony without a strong 

countervailing government interest) to Quinn’s case, we hold

that the Government did not engage in wrongdoing. We 

cannot conclude it deliberately distorted the factfinding 

process by delaying Johnson’s sentencing. No evidence 

demonstrates that the Government’s action had any effect on 

Johnson’s decision to invoke his Fifth Amendment right not 

to incriminate himself by his testimony. Nor did the 

Government keep clearly exculpatory testimony from 

Quinn’s trial by refusing to immunize Johnson. We thus 

affirm. 

I. Facts and Procedural History

A. The Bank Robbery 

On the morning of August 27, 2009, Quinn met 

Johnson in a parking lot at the Henderson Square shopping 

mall in King of Prussia, Pennsylvania. Quinn drove Johnson

across the parking lot to the National Penn Bank, located 

within the same shopping mall. While Johnson went into the 

bank, Quinn drove his car behind another store, and out of 

sight of those in the bank. 

Once inside, Johnson handed a check to one of the 

tellers. When she requested identification from Johnson, the 

teller realized Johnson had a gun pointed at her and that a 

note written on the back of the check demanded money. 

Johnson took several thousand dollars in cash from the teller 
7

and another bank employee transferring cash from the bank 

vault. Unknown to Johnson, the money he was given

contained a global positioning system (“GPS”) tracker hidden

inside a bundle of bills. Johnson left the bank and returned to 

Quinn, who was still waiting in his car behind the nearby 

store, and the two drove away.

Quinn and Johnson went to a nearby townhouse owned 

by Quinn’s aunt. There, Johnson discovered the GPS tracker 

and attempted to disable it by hitting it and submerging it in a 

bowl of water. He was unsuccessful. The Upper Merion 

Police Department used the tracker to locate the men at the 

townhouse, where both shortly surrendered. Police recovered 

a gun, the GPS tracker, and approximately $9,000 in cash. 

B. The Investigation and Indictment

Law enforcement officers interviewed both Quinn and 

Johnson that afternoon. Quinn told the officers that he did 

not know that Johnson planned to rob the National Penn 

Bank. Johnson confessed to the robbery, as well as another 

bank robbery he had committed a month earlier and a 

fraudulent check cashing scheme. He also told police that 

Quinn did not know he (Johnson) intended to rob National 

Penn. Beyond that statement, Johnson “was hesitant to talk 

about Quinn because Quinn is the brother of [Johnson’s]

fiancee.”

The United States Attorney for the Eastern District of 

Pennsylvania indicted both Quinn and Johnson for armed 

bank robbery in violation of 18 U.S.C. § 2113(d), and using 

and carrying a firearm during and in relation to a crime of 

violence in violation of 18 U.S.C. § 924(c). Johnson was also 
8

indicted for the earlier bank robbery and for being a felon in 

possession of a gun in violation of 18 U.S.C. § 922(g)(1). 

Johnson pled guilty to all of the charges in May 2010, and

was awaiting sentencing in August 2010 when Quinn’s trial 

was scheduled to begin.

C. Johnson’s Assertion of His Fifth Amendment 

Privilege

Prior to the start of Quinn’s trial, his counsel 

discovered that Johnson had been transferred to an out-ofstate prison. Quinn requested, and was granted, a 

continuance so that Johnson could be returned to 

Pennsylvania and be available to testify. 

In response to this continuance, the Government filed a 

motion to postpone Johnson’s sentencing. It apparently was 

concerned that Johnson, who had already pled guilty to the 

robbery, could shield Quinn from blame without any 

additional cost to himself by testifying that Quinn was not 

involved in that crime. By delaying Johnson’s sentencing 

until after his testimony, the Government contended it would 

retain the ability to present to the sentencing Court any 

testimony by Johnson it believed to be perjurious.

[I]f Keenan Quinn calls [Johnson] as a witness 

and [Johnson] does not invoke his right against 

self-incrimination, it is possible, if not probable, 

that [Johnson] will commit perjury. Thus . . . his 

testimony will likely have a direct effect on his 

[sentencing] guidelines and the Court’s analysis 

under 18 U.S.C. § 3553(a). 
9

Johnson’s only response to the Government’s motion was to 

inform the Court that if either “the codefendant’s counsel or 

the government attempts to call Mr. Johnson as a witness at 

the trial of the codefendant, Mr. Johnson will assert his right 

to remain silent under the Fifth Amendment.”

As his reply to the Government’s motion to delay and 

Johnson’s statement that he intended to invoke the Fifth 

Amendment, Quinn filed a motion in limine asking the Court 

to exercise its authority under our holding in Smith to 

immunize Johnson so he could testify on Quinn’s behalf 

without fear of prosecution or repercussion at sentencing. 

The Government opposed the motion. Following briefing and 

oral argument, the Court denied Quinn’s request, and 

declined to reconsider that ruling when Quinn renewed the 

motion at the close of evidence. 

D. Quinn’s Trial

At trial, the Government introduced phone records 

showing that Quinn called Johnson once the day before the 

robbery and five times in a little over two hours on the 

morning of the robbery. Evidence of these calls, though 

deleted from the call history on Quinn’s phone before it was 

taken by the police, was revealed through the phone 

company’s documentation. The Government also presented 

testimony from two of Quinn’s former cellmates, Anthony 

Bennett and Nicholas Mason. Bennett testified of 

conversations with Quinn whereby the latter had planned a 

crime in which he acted as the driver and hoped to beat the 

charges because his codefendant would “take all of the 

charges.” Mason testified that Quinn admitted that he and a 

codefendant planned a bank robbery where “[Quinn] stayed 
10

parked at a separate location so he would not be linked to the 

crime.”

Quinn testified in his own defense. He told the jury

that he called Johnson once on the morning of the robbery to 

make plans to meet for breakfast. He claimed that he began 

to drive Johnson to his aunt’s house, where they intended to 

spend the morning, when Johnson directed him to pull in 

front of the bank’s entrance. As he got out of the car, 

Johnson told Quinn to wait behind a nearby store. Quinn 

stated that he believed Johnson was going to cash a fraudulent 

check at the bank, something Johnson had done before, but 

did not know that Johnson was going to rob the bank at 

gunpoint. 

Johnson did not testify. His statement to police that 

Quinn was not aware of the planned robbery was excluded as 

hearsay.

After a four-day trial, the jury found Quinn guilty of 

aiding and abetting a bank robbery and carrying a firearm in 

relation to a crime of violence. His sentence was 147

months’ imprisonment and monetary penalties.

E. This Appeal

This appeal followed. Quinn argues that the District 

Court erred by not exercising its authority under Smith to 

immunize Johnson’s testimony, thus denying Quinn the 

opportunity to present an effective defense. He also claims

for the first time that the prosecution’s request to postpone 

Johnson’s sentencing until after Quinn’s trial was intended to 

induce Johnson to invoke his Fifth Amendment privilege, a 
11

deliberate distortion of the factfinding process and thus an act 

of prosecutorial misconduct. As a remedy, Quinn contends

his conviction should be vacated and the charges dismissed 

unless Johnson is given immunity to testify at a retrial. 

 In response to Quinn’s appeal, the Government 

questioned our unique jurisprudence in this area. We sua 

sponte elected to hear this case en banc to “reconsider the . . .

theory of judicial immunity” recognized in Smith. The parties 

filed supplemental briefs, and we heard argument en banc.

II. Judicial Use Immunity

A. Our Holding in Smith

In Smith, three defendants were charged with assault 

and robbery of a man named Phipps. The Government’s case 

centered on Phipps’ identification of the defendants as his 

assailants. During the investigation following the assault, 

however, a man named Sanchez told police that he and 

several others—none of whom was among the defendants—

were responsible for the crime. Smith, 615 F.2d at 966–67.

Defendants called Sanchez as a witness at their trial, 

but he refused to testify on the basis of his Fifth Amendment 

privilege against self-incrimination. Because he was a 

juvenile at the time of the offense, Sanchez was subject to the 

exclusive jurisdiction of the Virgin Islands Attorney General, 

who offered to grant immunity to Sanchez if, as a 

prosecutorial courtesy, the United States Attorney prosecuting 

the case consented. Id. at 967. When the U.S. Attorney 

refused to consent, the trial proceeded without Sanchez’s 
12

testimony or his hearsay statements to police, and all three

defendants were convicted. Id.

Citing our opinion in Morrison, 535 F.2d 223, we held 

that if the Government had refused immunity “with the 

deliberate intention of distorting the factfinding process, then 

the district court should enter a judgment of acquittal as to 

defendants . . . unless the government consents to grant 

statutory use immunity to [the witness].” Smith, 615 F.2d at 

969. Our Court in Smith called this “statutory immunity,” id., 

though it is more commonly referred to as the prosecutorial 

misconduct theory. While rarely the basis of a retrial order, 

this theory provides a valuable safeguard against 

prosecutorial overzealousness infringing on the fair trial

ensured to a criminal defendant. 

Smith went further and held that the trial court could

itself “grant judicial immunity to the witness” if necessary to 

“vindicate the defendant’s constitutional right to a fair trial.” 

Id. at 974. We held that court-granted immunity could be 

used to ensure that the defendant was able to present an 

effective defense if the Government inexplicably refused to 

immunize a defense witness with exculpatory and essential

testimony. We first considered this “effective defense”

theory in United States v. Herman, 589 F.2d 1191 (3d Cir. 

1978), but did not establish the test and remedy until two 

years later in Smith.

1

 We refer to this power as “judicial use 

 

1

The idea of immunizing a witness as necessary to secure the 

defendant’s due process right is often traced to a footnote in 

then-Judge Warren Burger’s opinion in Earl v. United States, 

361 F.2d 531, 534 n.1 (D.C. Cir. 1966). The theory that a 

defendant could have a due process right to witness testimony 
13

immunity” because it involves a court conferring immunity 

without a request from the Government. 

Smith recognized that the judicial grant of immunity

intruded on the Government’s statutory authority to immunize 

witnesses and prosecutorial discretion to prioritize 

enforcement of the laws. Thus we held that “opportunities for 

judicial use of this immunity power must be clearly limited.”

Smith, 615 F.2d at 972. We created a five-part test—witness 

immunity could be granted only if “[1] properly sought in the 

district court; [2] the defense witness [is] available to testify; 

[3] the proffered testimony [is] clearly exculpatory; [4] the 

testimony [is] essential; and [5] there [are] no strong 

governmental interests which countervail against a grant of 

immunity.” Id. These factors balance the Government’s 

discretion in prosecutorial decisions and the defendant’s right 

to present a meaningful defense.

B. Rejection of Judicial Use Immunity

As noted, we are the only Court of Appeals that has 

recognized judicial use immunity for witnesses. United 

 

also gained traction in academic literature. See, e.g., Donald 

Koblitz, Note, “The Public Has a Claim to Every Man’s 

Evidence”: The Defendant’s Constitutional Right to Witness 

Immunity, 30 Stan. L. Rev. 1211 (1978); Note, The Sixth 

Amendment Right to Have Use Immunity Granted to Defense 

Witnesses, 91 Harv. L. Rev. 1266 (1978); Helen M. McCue, 

Note, Separation of Powers and Defense Witness Immunity, 

66 Geo. L.J. 51 (1977); Barbara A. Reeves, Note, A ReExamination of Defense Witness Immunity: A New Use for 

Kastigar, 10 Harv. J. on Legis. 74 (1972). 
14

States v. Serrano, 406 F.3d 1208, 1217 (10th Cir. 2005) 

(“Every other Circuit, save the Third, has . . . held a district 

court does not have the inherent authority to grant a defense 

witness use immunity.”). Other Courts of Appeals have 

adopted the prosecutorial misconduct theory, and evaluate

whether the Government may be required to immunize a 

witness if necessary to protect the defendant’s right to present 

an effective defense; but none authorizes a district court to

grant immunity on its own authority. See, e.g., Curtis v. 

Duval, 124 F.3d 1 (1st Cir. 1997); United States v. Turkish, 

623 F.2d 769, 772 (2d Cir. 1980); United States v. 

Moussaoui, 382 F.3d 453 (4th Cir. 2004); United States v. 

Thevis, 665 F.2d 616 (5th Cir. Unit B 1982), superseded on

other grounds by Fed. R. Evid. 804(b)(6); United States v. 

Talley, 164 F.3d 989 (6th Cir. 1999); United States v. 

Herrera-Medina, 853 F.2d 564 (7th Cir. 1988); United States 

v. Bowling, 239 F.3d 973 (8th Cir. 2001); United States v. 

Westerdahl, 945 F.2d 1083 (9th Cir. 1991); Serrano, 406 F.3d 

at 1217–18; United States v. DiBernardo, 880 F.2d 1216 

(11th Cir. 1989); United States v. Perkins, 138 F.3d 421 (D.C. 

Cir. 1998). They have cited concerns of judicial competency 

to weigh immunity decisions and the Executive Branch’s sole

authority to immunize under the federal immunity statute, 18 

U.S.C. §§ 6002, 6003. See, e.g., United States v. Capozzi, 

883 F.2d 608, 614 (8th Cir. 1989) (“Every court of appeals 

which has considered the question has rejected the Third 

Circuit’s Smith holding as being a violation of the doctrine of 

separation of powers.”). Judicial use immunity has also been

questioned by members of our Court. United States v. 

Bazzano, 712 F.2d 826, 851 (3d Cir. 1983) (en banc) (Adams,

J., with Hunter and Becker, JJ., dissenting) (“Smith may have 

expanded judicial power too far.”). 
15

It is in this context that we revisit that aspect of 

Smith’s holding whereby courts have the inherent authority to 

immunize a defense witness. 

C. Reconsidering Judicial Use Immunity

The Fifth Amendment guarantees that “[n]o person 

shall . . . be deprived of life, liberty, or property, without due 

process of law.” U.S. Const. amend. V. The Sixth 

Amendment guarantees a criminal defendant’s right “to have 

compulsory process for obtaining witnesses in his favor.” Id.

amend. VI. Fundamentally, “the Constitution guarantees 

criminal defendants a meaningful opportunity to present a 

complete defense.” Crane v. Kentucky, 476 U.S. 683, 690 

(1986) (internal quotation marks omitted); Chambers v. 

Mississippi, 410 U.S. 284, 294 (1973) (“The right of an 

accused in a criminal trial to due process is, in essence, the 

right to a fair opportunity to defend against the State’s 

accusations.”).

The Smith Court based its judicial immunity remedy 

on the conclusion that the Fifth Amendment’s Due Process 

Clause includes a right to present an effective defense. 

Although it cited the Sixth Amendment’s right to compulsory 

process, that alone does not entitle a defendant to request 

immunity for his witnesses. United States v. ValenzuelaBernal, 458 U.S. 858, 867 (1982) (“[T]he Sixth Amendment 

does not by its terms grant to a criminal defendant the right to 

secure the attendance and testimony of any and all 

witnesses.”); Washington v. Texas, 388 U.S. 14, 19 (1967)

(“The right to offer the testimony of witnesses, and to compel 

their attendance, if necessary, is in plain terms the right to 

present a defense . . . .”); Diggs v. Owens, 833 F.2d 439, 444 
16

(3d Cir. 1987) (“In general a defendant’s Sixth Amendment 

right of compulsory process gives way when a witness he has 

subpoenaed invokes his Fifth Amendment privilege against 

self-incrimination.”); Moussaoui, 382 F.3d at 467 (“[A] 

defendant has no Sixth Amendment right to such 

testimony.”).

We held in Smith that a court could bestow immunity 

on a defense witness to guard a defendant’s constitutional 

right to present an effective defense. On revisiting the issue, 

we no longer believe this is a permissible use of judicial 

authority. Congress has given the Executive Branch the sole 

authority to immunize witnesses; giving that power to courts

intrudes on prosecutorial decision-making and goes beyond 

judicial expertise. Moreover, we think the defendant’s right 

to due process is protected by retaining the effective defense 

test as a complement to our prosecutorial misconduct inquiry.

1. The Statutory Basis of Immunity

Immunity is a creation of the legislature, the body that

defines criminal offenses and their sanctions. It removes

“those sanctions which generate the fear justifying invocation 

of the privilege,” Ullmann v. United States, 350 U.S. 422, 431

(1956), and is akin to “an act of general amnesty,” Brown v. 

Walker, 161 U.S. 591, 601 (1896). 

Under the federal witness immunity statute, “no 

testimony or other information compelled . . . (or any 

information directly or indirectly derived from such testimony 

or other information) may be used against the witness in any 

criminal case, except a prosecution for perjury, giving a false 

statement, or otherwise failing to comply with the order.” 18 
17

U.S.C. § 6002. This is known variously as use and derivative 

use, or use and fruits, immunity (shortened to use immunity 

throughout this opinion). Congress has given the Attorney 

General the authority to exchange the protection of immunity 

for otherwise incriminating testimony when, “in his 

judgment,” a witness’s testimony “may be necessary to the 

public interest.” § 6003(b). Because this protection “is 

coextensive with the scope of the [Fifth Amendment] 

privilege against self-incrimination,” a Court can hold an 

immunized witness in contempt for refusal to testify. 

Kastigar v. United States, 406 U.S. 441, 453 (1972).

Congress granted this authority to the Executive 

Branch because immunity is a prosecutorial tool. Often those 

with pertinent knowledge about criminal offenses have 

engaged in unlawful behavior themselves. Granting

immunity enables the Government to elicit testimony that 

would otherwise be protected by the Fifth Amendment 

privilege against self-incrimination.

Congress has not given criminal defendants any 

similar power to seek immunity for their witnesses. Nor has 

it authorized the federal courts to immunize a witness.

Instead, under § 6002 a district court’s role is to grant 

immunity when it is requested by the Attorney General or his 

designee. Though a court reviews the Government’s request 

for procedural compliance with the statute, it does not 

consider whether the Government has correctly determined if 

immunity is in the public interest. Pillsbury Co. v. Conboy, 

459 U.S. 248, 254 n.11 (1983) (“Congress foresaw the courts 

as playing only a minor role in the immunizing 

process . . . .”); Herman, 589 F.2d at 1201 (“There 

is . . . overwhelming judicial and legislative authority for the 
18

proposition that review on the merits of a federal prosecutor’s 

decision to grant immunity is barred by statute.”); see also 

United States v. Taylor, 728 F.2d 930, 934 (7th Cir. 1984) 

(describing this review as “ministerial”). 

There are good reasons for immunity decisions to 

reside with the Executive Branch. Often the decision to grant 

or deny immunity impinges on the Government’s “broad 

discretion as to whom to prosecute.” Wayte v. United States, 

470 U.S. 598, 607 (1985) (internal quotation marks omitted). 

In any later prosecution, the Government bears a “‘heavy 

burden’” because it must “prove that its evidence against the 

immunized witness has not been obtained as a result of his 

immunized testimony.” Turkish, 623 F.2d at 775 (quoting 

Kastigar, 406 U.S. at 461). In some cases, the Government 

may have already assembled the evidence it needs, or it can 

“sterilize” the immunized testimony by isolating those 

investigating or prosecuting the witness from any 

incriminating information provided through his testimony. 

Smith, 615 F.2d at 973. But if these precautions are 

unsuccessful or unavailable, a court’s granting immunity to a

witness to secure another’s criminal conviction may prevent 

the Government from ever prosecuting the witness for his 

own criminal behavior. 

Courts are not in the best position to decide these 

prosecutorial tradeoffs. “Such factors as the strength of the 

case, the prosecution’s general deterrence value, the 

Government’s enforcement priorities, and the case’s 

relationship to the Government’s overall enforcement plan are 

not readily susceptible to the kind of analysis the courts are 

competent to undertake.” Wayte, 470 U.S. at 607; see 

Moussaoui, 382 F.3d at 467 (“Decisions to grant or deny 
19

immunity are intimately tied to decisions regarding which 

perpetrators of crimes will be prosecuted, a core aspect of the 

Executive’s duty to enforce the laws.”); In re Daley, 549 F.2d 

469, 479 (7th Cir. 1977) (“[T]he relative importance of 

particular testimony to federal law enforcement interests is a 

judgmental rather than a legal determination, one remaining 

wholly within the competence of appropriate executive 

officials.”). Giving judges the power to immunize witnesses

“would carry the courts into policy assessments which are the 

traditional domain of the [E]xecutive [B]ranch.” Thevis, 665 

F.2d at 639. As Congress has given the power to immunize a 

witness solely to the Executive Branch, it is not a power 

courts can exercise.

2

 

2 Our sister Circuits have also expressed a fear that judicially 

granted immunity “would be subject to abuse” by criminal 

defendants who could seek immunity for one another, each 

testifying that the other was not involved, or that one criminal 

defendant could take the fall for coconspirators by taking full 

responsibility at the others’ trials. Thevis, 665 F.2d at 639–

40; Turkish, 623 F.2d at 775. Though these witnesses subject 

themselves to perjury prosecution, the perjury statutes likely 

carry far lower sanctions, and therefore deterrence, than the 

charged offenses. Thevis, 665 F.2d at 640 n.27 (“Nor are we 

convinced that perjury prosecutions are an adequate deterrent. 

Successful perjury prosecutions are not common, and in many 

cases the penalty for the substantive crime will far surpass 

perjury penalties.”). Although we have recognized judicial 

use immunity for over thirty years and these fears do not 

appear as a problem to date, we recognize that the possibility 

of this kind of abuse further highlights the limits of judicial 

expertise in this area. 
20

2. The Lack of Support for Judicial Use 

Immunity

In Smith, we justified judicial use immunity as 

“new only in the sense of its application” in that context. 615 

F.2d at 971. We said that “[b]oth the Supreme Court [in 

Simmons v. United States, 390 U.S. 377 (1968),] and this 

[C]ourt [in In re Grand Jury Investigation, 587 F.2d 589 (3d 

Cir. 1978), and United States v. Inmon, 568 F.2d 326 (3d Cir. 

1977),] have previously found an inherent judicial power to 

grant witness immunity.” Id. We now believe this was too 

expansive a reading of those cases. Simmons, and our cases 

applying its holding, Grand Jury and Inmon, permit a court to 

exclude a criminal defendant’s earlier testimony from trial in 

narrow circumstances. This differs significantly from

granting immunity to a defense witness when that witness has 

invoked the Fifth Amendment.

In Simmons, the Supreme Court held that a defendant’s 

testimony in support of his motion to suppress evidence on 

Fourth Amendment grounds could not be admitted against

him on the issue of guilt at his later trial, as it is “intolerable 

that one constitutional right should have to be surrendered in 

order to assert another.” 390 U.S. at 394. We applied the 

logic of Simmons to hold that a defendant’s testimony offered

to gain the protection of the Speech and Debate Clause,

Grand Jury, 587 F.2d at 597, and the Double Jeopardy 

prohibition, Inmon, 568 F.2d at 333, could similarly not be 

used to prove his guilt at a subsequent trial.

Although the Court’s opinion in Simmons never uses 

the word “immunity,” courts—including our own—have 

analogized Simmons’ protection of testimony given at a 
21

suppression hearing to a grant of immunity. See, e.g., United 

States v. Perry, 788 F.2d 100, 116 (3d Cir. 1986) (noting that 

“Simmons v. United States authorizes the grant of use 

immunity,” thus a defendant could testify at a bail hearing

without fear of incrimination); United States v. Bryser, 95 

F.3d 182, 186 (2d Cir. 1996) (holding that “use immunity 

under Simmons” was not available at a resentencing hearing).

Simmons created an exclusionary rule (that is, it

excludes a defendant’s testimony in an earlier hearing from 

being used at trial against him) when the criminal defendant 

would otherwise have to waive at the hearing his Fifth 

Amendment privilege against self-incrimination. The 

Supreme Court has not extended Simmons beyond those facts. 

United States v. Snipes, 611 F.3d 855, 866 (11th Cir. 2010). 

Simmons’ reasoning does not reach the facts of Smith; neither 

the defendants in that case nor the defense witness faced a 

conflict between two constitutional rights. In addition, the 

protection afforded by the Supreme Court under Simmons

(the exclusion from his trial of a criminal defendant’s 

testimony at a prior suppression hearing) does not present the 

same intrusion on prosecutorial discretion as does a judicial 

grant of immunity to a defense witness. In other words,

Simmons’ exclusionary rule does not extend a court’s power

to invade the prosecutorial decisions discussed above. 

Any possibility that the Supreme Court authorized in 

Simmons a general judicial authority to confer use immunity 

for non-defendant witnesses is undermined by its subsequent

discussions of the authority to immunize witnesses. In cases 

addressing grants of immunity, it is clear that the Court

believes only the Executive Branch, and not the Judiciary, has

the authority to immunize a witness. In Pillsbury, the Court 
22

held that a witness in a civil suit could invoke the Fifth 

Amendment during a deposition in which he was asked 

questions identical to those asked and answered under 

Government-sought immunity before a grand jury. 459 U.S. 

248 (1983). Holding that the deposition testimony was not 

“derived from” the immunized testimony and hence not 

protected by the grant of immunity, the Court held that the 

trial court could not compel the witness’s incriminating

answers because “only the Attorney General or a designated 

officer of the Department of Justice has authority to grant use 

immunity,” and “Congress gave certain officials in the 

Department of Justice exclusive authority to grant 

immunities.” Id. at 248, 253–54, 261 (emphasis added and 

footnote omitted). 

Similarly, in United States v. Doe the Government 

sought to compel document production through a promise not 

to prosecute but without obtaining immunity under the federal 

immunity statute. 465 U.S. 605 (1984). The Supreme Court 

declined “to adopt a doctrine of constructive use immunity,”

and refused to “extend the jurisdiction of courts to include 

prospective grants of use immunity in the absence of the 

formal request that the statute requires.” Id. at 616. It

explained that, under Pillsbury, prosecutors had the exclusive 

authority to grant immunity, as that decision “necessarily 

involves a balancing of the Government’s interest in 

obtaining information against the risk that immunity will 

frustrate the Government’s attempts to prosecute the subject 

of the investigation. Congress expressly left this decision 

exclusively to the Justice Department.” Id. at 616–17 

(citation omitted). In a more recent discussion of immunity, 

the Court referred repeatedly to the Executive Branch’s 

authority to immunize a witness. See United States v. Balsys, 
23

524 U.S. 666, 682–83 (1998) (“[T]he government has an 

option to exchange the stated privilege for an immunity to 

prosecutorial use of any compelled inculpatory 

testimony. . . . The only condition on the government when it 

decides to offer immunity in place of the privilege to stay 

silent is the requirement to provide an immunity as broad as 

the privilege itself. . . . [T]he immunity option open to the 

Executive Branch could be exercised only on the 

understanding that the state and federal jurisdictions were as 

one.” (citation omitted)).

This language is no doubt dicta. Yet “we cannot 

lightly ignore the force of Supreme Court dicta.” Morrow v.

Balaski, 719 F.3d 160, 169 (3d Cir. 2013) (en banc). “The 

Supreme Court uses dicta to help control and influence the 

many issues it cannot decide because of its limited docket.” 

In re McDonald, 205 F.3d 606, 612 (3d Cir. 2000). 

“Appellate courts that dismiss these expressions . . . increase 

the disparity among tribunals . . . and frustrate the 

evenhanded administration of justice . . . .” Id. at 612–13 

(internal quotation marks omitted). 

3. Judicial Use Immunity and Kastigar

Quinn urges us to uphold judicial use immunity,

arguing that courts do not need authority to “grant” immunity. 

Instead, he believes the judicial power to compel testimony 

necessary to a defendant’s defense, on its own, carries 

immunity for that testimony. Quinn reads Kastigar v. United 

States, 406 U.S. 441 (1972), to hold that testimony, once 

compelled, is necessarily immunized. He explains “the SelfIncrimination Clause by its own force confers immunity for 
24

direct and indirect uses of the compelled testimony 

against . . . that witness.” Appellant’s Supplemental Br. at 6. 

That is not correct. In Kastigar, two witnesses were 

immunized under 18 U.S.C. § 6002 but refused to testify 

before a grand jury. 406 U.S. at 442. They contended that 

the statutory protection was not sufficient to supplant the 

privilege and compel their testimony. The District Court held 

them in contempt and the Supreme Court upheld that order. 

Id. at 453. “[S]uch immunity from use and derivative use is 

coextensive with the scope of the privilege against selfincrimination, and therefore is sufficient to compel testimony 

over a claim of the privilege.” Id. Testimony that would 

otherwise incriminate can only be compelled—that is, sought 

subject to contempt if not given—after the threat of criminal

sanction is lifted. That testimony is not automatically 

immunized because it is compelled; rather, if the witness 

claims the privilege, his testimony can be compelled because 

the federal immunity statute protects him from incrimination

as a result of his testimony, the same protection afforded by 

the Fifth Amendment. 

As we discussed above, only the Government has 

statutory authority to seek immunity. And only when 

testimony is protected by immunity granted by the 

Government can a court compel that testimony. The

authority of a court to immunize a witness cannot be assumed 

from Kastigar. 

* * * * *

We know of no precedent (save Smith) to support use 

immunity grants by the Judiciary, as that right is reserved to 
25

the Executive Branch. In addition, we do not believe that 

judicial use immunity is necessary to protect the 

constitutional rights of the accused. As explained in the next 

section, we believe that, when understood in its historical 

context, Smith proscribed prosecutorial misconduct and the

test we created there to assess claims of misconduct remains

both useful and worth keeping. Thus, though we abandon 

judicial use immunity as a remedy, we keep the protection of 

due process provided through the test created in Smith. 

III. The Prosecutorial Misconduct Theory

The prosecutorial misconduct theory we recognized 

prior to Smith holds that the Government violates a 

defendant’s due process right to a fair trial if it acts with the 

deliberate intention of distorting the factfinding process, such

as by interfering with a defense witness through threats and 

intimidation. Because it looks to Government action, this test 

is difficult to apply when the Government declines to grant 

immunity to a defense witness. Smith crafted a new five-part 

test to address instances of Government refusal to immunize,

with the aim of ensuring that a defendant is able to present a 

defense free from improper Government intrusion. 

A. Our Holding in Morrison

The first case in our Circuit involving the prosecutorial 

misconduct theory was United States v. Morrison, 535 F.2d 

223 (3d Cir. 1976). We held that the Government’s 

interference with a defense witness’s testimony violated the 

defendant’s guarantee of due process. Id. at 228. Morrison’s 

girlfriend intended to testify that she, and not he, engaged in 

the charged criminal conspiracy to distribute hashish. Over 
26

the course of the trial, the prosecutor sent several messages to 

the witness warning her that she could be charged for the drug 

crimes and perjury on the basis of her testimony. Id. at 225. 

The night before her testimony, the prosecutor subpoenaed 

the witness and interviewed her in his office. Accompanied 

by the law enforcement officers involved in the case, he again 

warned her of the dangers of testifying. These warnings had 

their intended effect. When called to testify, Morrison’s 

girlfriend invoked her Fifth Amendment privilege against 

self-incrimination. Id. at 226.

We held that the prosecutor’s “repeated warnings[,]

which culminated in a highly intimidating personal 

interview,” had “interfered with the voluntariness of [the 

witness’s] choice and infringed [the] defendant’s

constitutional right to have her freely-given testimony.” Id. at 

227–28. Due process protects the defendant’s “right . . . to 

have [his] witness available as he finds him.” United States v. 

Herman, 589 F.2d 1191, 1199 (3d Cir. 1978). We vacated 

Morrison’s conviction and held that, if the witness invoked a 

privilege against self-incrimination during a retrial, the 

charges against Morrison should be dismissed unless the 

Government immunized the witness’s testimony under 18 

U.S.C. § 6002. Morrison, 535 F.2d at 229.

Our holding in Morrison followed from the Supreme 

Court’s holding in Webb v. Texas, 409 U.S. 95 (1972). There,

a trial court 

gratuitously singled out [the only defense]

witness for a lengthy admonition on the dangers 

of perjury. . . . [T]he judge implied that he 

expected [the witness] to lie, and went on to 
27

assure him that if he lied, he would be 

prosecuted and probably convicted for perjury, 

that the sentence for that conviction would be 

added on to his present sentence, and that the 

result would be to impair his chances for parole. 

Id. at 97. The Supreme Court held that the judge’s remarks 

“effectively drove that witness off the stand, and thus 

deprived the petitioner of due process of law under the 

Fourteenth Amendment.” Id. at 98. 

Other courts have interpreted Webb similarly to hold 

that “[v]arious prosecutorial and judicial actions aimed at 

discouraging defense witnesses from testifying deprive a 

defendant of [his due process] right.” United States v. 

Emuegbunam, 268 F.3d 377, 400 (6th Cir. 2001); see also

United States v. Hooks, 848 F.2d 785, 799 (7th Cir. 1988)

(“‘[The prosecutor]’s warnings concerning the dangers of 

perjury cannot be emphasized to the point where they threaten 

and intimidate the witness into refusing to testify.’” (quoting 

United States v. Blackwell, 694 F.2d 1325, 1334 (D.C. Cir. 

1982))); United States v. MacCloskey, 682 F.2d 468, 479 (4th 

Cir. 1982) (prosecutor’s “eleventh hour call” to primary 

defense witness “suggesting that she would be well-advised 

to remember the Fifth Amendment” is a due process violation 

under Webb that entitles the defendant to a new trial). 

B. Prosecutorial Misconduct Beyond Morrison

Following Morrison, we defined prosecutorial 

misconduct as actions taken “with the deliberate intention of 

distorting the judicial factfinding process.” Smith, 615 F.2d 

at 968; Herman, 589 F.2d at 1204. This deliberate distortion
28

test applies when the Government has taken steps to interfere 

with the testimony of a witness who would otherwise be 

available to the defense. For example, the prosecution has 

engaged in misconduct if the defendant can show that the 

Government’s “[i]ntimidation or threats . . . dissuade[d] a 

potential witness from testifying”—that is, “the 

[G]overnment’s conduct . . . ‘substantially interfered’ with a 

witness’s choice to testify.” Lambert v. Blackwell, 387 F.3d 

210, 260 (3d Cir. 2004).

But we have also used the deliberate distortion test in 

situations where prosecutors did not engage in overt threats or 

intimidation. In Herman, we considered whether the 

Government’s selective immunization of prosecution 

witnesses, but not defense witnesses, violated the defendant’s 

due process rights. 589 F.2d at 1203–04. Because the 

Government’s decision to immunize some witnesses and not 

others was based on its decision to prosecute them, and not on 

their testimony at Herman’s trial, we discerned no 

misconduct. Id. In Smith, we asked whether the prosecutor’s 

refusal to permit a defense witness to testify under a grant of 

immunity, when there was no interest in prosecuting him, was 

a deliberate effort to distort the factfinding process. Smith, 

615 F.2d at 969. We recognized that when the Government 

declines to seek immunity for a defense witness, it is difficult 

for a defendant to prove that the prosecution acted with the 

deliberate intention of distorting the factfinding process. 

Thus in Smith we also created a new five-factor test that

focused on whether the defendant “is prevented from 

presenting exculpatory evidence which is crucial to his case.” 

Id. 
29

Although we characterized this test as distinct from an 

inquiry into prosecutorial misconduct, it is nonetheless about 

the Government’s trial decisions. We wanted to know if the 

prosecutor was keeping exculpatory and essential testimony 

from trial solely to gain a tactical advantage against the 

accused. If there were a governmental reason, unrelated to 

the defendant’s trial, for refusing immunity, we would not 

interfere with that decision. If, however, the Government had 

no strong reason to keep exculpatory testimony from trial, we 

could overturn a resulting conviction. See United States v. 

Turkish, 623 F.2d 769, 777 (2d Cir. 1980) (“[Smith] was 

simply an instance of a prosecutor interfering, for no apparent 

reason, to suppress evidence that was about to become 

available to the accused.”). A proceeding “[t]hat casts the 

prosecutor in the role of an architect,” instead of participant, 

does not “comport with standards of justice.” Brady v. 

Maryland, 373 U.S. 83, 88 (1963).

Other courts have not distinguished, as we did in 

Smith, the prosecution’s interference with a witness from its 

refusal to immunize a witness. Instead, they have treated the 

Government’s refusal to grant immunity as a question of 

misconduct. Blissett v. Lefevre, 924 F.2d 434, 442 (2d Cir. 

1991) (“Prosecutorial overreaching may also involve 

deliberate denial of immunity for the purpose of withholding 

exculpatory evidence and gaining a tactical advantage 

through such manipulation.”); United States v. Angiulo, 897 

F.2d 1169, 1192 (1st Cir. 1990) (“[T]he government could 

intentionally distort the fact-finding process by deliberately 

withholding immunity from certain prospective defense 

witnesses for the purpose of keeping exculpatory evidence 

from the jury.”); Hooks, 848 F.2d at 802 (considering whether 

“the government’s withholding of immunity distorted the 
30

fact-finding process by keeping exculpatory evidence from 

the jury”); United States v. Frans, 697 F.2d 188, 191 (7th Cir. 

1983) (requiring a defendant to show “that the government 

intended to distort the judicial fact-finding process” by 

refusing to immunize a defense witness after immunizing a 

prosecution witness). 

The five factors considered in Smith remain

analytically helpful, as they capture those situations where the 

Government, for tactical reasons, has used its power to 

threaten prosecution and withhold immunity to keep 

exculpatory and essential testimony from trial for no strong 

countervailing reason. This test fleshes out, and thus 

complements, Morrison’s metric of deliberate distortion. For 

good reason this test also requires a more exacting showing 

than does the broader misconduct test. When a defendant 

alleges that the Government’s refusal to immunize resulted in 

an unfair trial, he is challenging its statutory discretion in his

case and possibly others. If the defendant can show, as a 

prima facie matter, a witness’s testimony is available, clearly

exculpatory, and essential—in effect showing that the 

prosecutor’s actions have impaired the ability to present an 

effective defense—we will consider the due process concerns 

raised regarding the Government’s discretion to grant or deny 

immunity. The five-factor test aids this inquiry for 

prosecutorial misconduct, and we continue its use. 

C. The Remedy

Once Smith’s five-part test is understood as a gauge of

prosecutorial misconduct, the remedy for such a finding

follows easily. It is vacating the conviction and allowing a 

new trial where the Government can elect to exercise its 
31

statutory authority to obtain a grant of immunity for the 

witness. United States v. Pennell, 737 F.2d 521, 526 (6th Cir. 

1984) (“The recommended remedy in such cases has been 

that a court . . . set aside the conviction and remand the case 

to afford the prosecutor an opportunity to immunize . . . .”). 

If the Government refuses to immunize the witness in 

violation of the defendant’s due process right, the trial court 

can dismiss the charges against the defendant.

3

 

Courts sometimes refer to this remedy as “compelling 

the Government to immunize the witness,” id. at 468, but that 

is imprecise. Dismissing the charges unless the witness is 

immunized leaves prosecutorial decisions in the hands of the 

Government. It may grant immunity to the witness and 

attempt to convict the defendant in a fair trial, or it may 

decide that denying the witness immunity is more important 

to its goals than seeking that conviction. But the remedy does 

not compel the Government to do anything. It simply 

prevents prosecutors from obtaining a conviction through a 

process that lacks the fairness afforded by due process. 

United States v. Hooks, 848 F.2d 785, 799 (7th Cir. 1988)

(“[T]he prosecutor’s power to seek or to refuse to seek 

immunity is limited by the constitutional right to due process 

of the law.”).

 

3 While we do not deal in this opinion with a possible 

alternative to dismissal, we note the possibility in the rare 

case that another cure could correct the distortive effect. See, 

e.g., United States v. Moussaoui, 382 F.3d 453, 476–77 (4th 

Cir. 2004) (appropriate substitute for witness’s testimony 

made available, so dismissal of charges not necessary).
32

D. Bad Faith

The Government argues that any test for a due process 

violation must require the defendant to show bad faith on the 

part of the Government. See United States v. Santtini, 963 

F.2d 585, 596–97 (3d Cir. 1992) (“As a general matter, even 

when actions by the prosecution appear to deprive a criminal 

defendant of his constitutional right to present a defense, no 

remedy will lie for such infringement absent a showing that 

the government has caused the unavailability of material 

evidence and has done so in bad faith.”). The element of bad 

faith, however, does not require a defendant to show specific

intent on the part of the Government to interfere with his due 

process rights. See Morrison, 535 F.2d at 227 (“The good 

faith of the [prosecutor] would be relevant if he were charged 

with violation of 18 U.S.C. § 1503[,] which makes the 

intimidation of a federal witness a criminal offense. It is not, 

however, relevant to an inquiry into whether a defendant was 

denied his constitutional right.” (emphases in original)). 

Our concern is with the effect of the prosecutor’s 

actions on the process afforded to the defendant. “The Due 

Process Clause addresses the defendant’s right to a fair trial, 

not just whether the government intended to deny the 

defendant his rights.” United States v. Straub, 538 F.3d 1147, 

1160 (9th Cir. 2008). “If the suppression of evidence results 

in constitutional error, it is because of the character of the 

evidence, not the character of the prosecutor.” United States 

v. Agurs, 427 U.S. 97, 110 (1976). Courts should protect 

against deliberate wrongdoing by prosecutors and, in those 

rare cases where it arises, overzealous advocacy that distorts 

the factfinding function of a criminal trial. 
33

That said, prosecutorial misconduct is an area of the 

law requiring sensitivity. Courts should be hesitant, absent a 

strong showing by the defense, to determine that the 

Government has engaged in misconduct by exercising its 

prosecutorial discretion and withholding immunity from a 

witness.

* * * * *

To summarize, judicial use immunity impinges on the 

separation of powers between the Executive and Judicial 

Branches of our Federal Government. The grant of witness 

immunity, reserved by statute to the Executive Branch, does 

not also reside with the Judiciary. We overturn that portion 

of our holding in Smith that recognizes the authority of courts 

to confer immunity on a witness. But we keep the test we 

created in that case, which we now recognize as 

supplementing our deliberate distortion test for prosecutorial 

misconduct. The appropriate remedy if a defendant can prove 

misconduct is to allow the Government to seek immunity for 

the witness at retrial or have the charges dismissed. With this 

revised legal framework, we turn to Quinn’s challenge to his 

conviction.

IV. Quinn’s Appeal

In the District Court, Quinn sought immunity for 

Johnson to testify, claiming that Johnson’s testimony was 

necessary for him to present an effective defense. Denying 

that immunity, Quinn contends, is a due process violation 

requiring a new trial. “Ordinarily we review a denial of a 

motion for a new trial under an abuse of discretion standard.” 

United States v. Joseph, 996 F.2d 36, 39 (3d Cir. 1993); cf.
34

United States v. Mike, 655 F.3d 167, 173 (3d Cir. 2011) 

(“Ultimately, the question of whether clearly exculpatory 

evidence is necessary to present an effective defense is a 

decision calling upon the sound judgment of the district court 

judge in a position to listen to the witnesses and evaluate the 

tenor of trial narratives.”). When the alleged violation 

includes “issues of law and fact[,] . . . we review the district 

court’s legal conclusions on a de novo basis and its factual 

findings under the clearly erroneous standard.” Joseph, 996 

F.2d at 39; see United States v. Risha, 445 F.3d 298, 303 (3d 

Cir. 2006). 

On appeal, Quinn argues for the first time that the

prosecution engaged in misconduct by interfering with 

Johnson’s testimony. He alleges that the Government’s 

motion to delay Johnson’s sentencing until after Quinn’s trial 

caused Johnson to invoke the Fifth Amendment and refuse to 

testify. Yet before trial Quinn expressly disclaimed an 

argument that the prosecution engaged in misconduct. At 

argument on his motion in limine to have Johnson immunized 

by the Court, Quinn’s counsel agreed that the prosecutorial 

misconduct theory was not at issue because Quinn did not 

allege “the government [was] doing anything improper.” 

Because he raises this argument for the first time on 

appeal, we review for plain error. Fed. R. Crim. P. 52(b); 

Puckett v. United States, 556 U.S. 129, 135 (2009). We 

follow the four-step inquiry set out in United States v. Olano, 

507 U.S. 725, 732–36 (1993). “First, there must be an error 

or defect—some sort of deviation from a legal rule . . . .” 

Puckett, 556 U.S. at 135 (alteration and internal quotation 

marks omitted). “Second, the legal error must be clear or 

obvious, rather than subject to reasonable dispute.” Id.
35

“Third, the error must have affected the appellant’s 

substantial rights, which in the ordinary case means he must 

demonstrate that it ‘affected the outcome of the district court 

proceedings.’” Id. (quoting Olano, 507 U.S. at 734). Even 

when all three of these conditions are satisfied, there is a 

fourth step. “[W]e will exercise our discretion to correct the 

unpreserved error only if . . . a miscarriage of justice would 

otherwise result, that is, if the error seriously affected the 

fairness, integrity or public reputation of judicial 

proceedings.” United States v. Corso, 549 F.3d 921, 929 (3d 

Cir. 2008) (internal quotation marks and alteration omitted).

A. Refusal to Immunize Johnson’s Testimony

We repeat for ease of reference that, to prove a due 

process violation on the basis of the Government’s refusal to 

immunize a defense witness, the defendant must show the 

following five elements. “[1] [I]mmunity must be properly 

sought in the district court; [2] the defense witness must be 

available to testify; [3] the proffered testimony must be 

clearly exculpatory; [4] the testimony must be essential; and 

[5] there must be no strong governmental interests which 

countervail against a grant of immunity.” Smith, 615 F.2d at 

972. The first two are not disputed. Quinn requested that 

Johnson be immunized and he was available to testify. We 

note, however, that there is no evidence that Quinn directed 

his immunity request to the Government. Going forward, 

defendants must seek immunity for their witnesses from the 

Government, not the district courts. In the unusual posture of 

this case—where we have kept the analytical test but no 

longer recognize a district court’s ability to immunize a 

witness—we will assume, from the Government’s opposition 
36

to Quinn’s motion in limine, that it would have refused to 

immunize Johnson if asked.

We start with the requirement that Quinn show that 

Johnson’s testimony is clearly exculpatory, i.e., that it would 

exonerate or free him of guilt or blame. Testimony that is “at 

best speculative,” United States v. Ammar, 714 F.2d 238, 251 

n.8 (3d Cir. 1983), “severely impeached” by the witness’s 

prior inconsistent statement(s), United States v. Perez, 280 

F.3d 318, 348 (3d Cir. 2002), ambiguous on its face, Smith, 

615 F.2d at 972, or “even if believed, would not in itself 

exonerate [the defendant],” United States v. Lowell, 649 F.2d 

950, 965 (3d Cir. 1981) (emphasis omitted), is not clearly 

exculpatory.

Quinn and Amicus Curiae, the National Association of 

Criminal Defense Lawyers, urge us to be less exacting in our 

requirement that evidence be clearly exculpatory. They argue

that immunity should be available if the evidence is 

“materially favorable to the defense on the issue of guilt,”

Appellant’s Supplemental Br. at 19, or “could contribute 

substantially to raising a reasonable doubt,” Amicus Br. at 

11. We continue to be guided (as was the Smith Court) by the 

Supreme Court’s holding in Chambers v. Mississippi. It

required the State of Mississippi to abrogate otherwise 

appropriate evidentiary rules when they prevented the 

defendant from presenting essential testimony. 410 U.S. 284 

(1973); see also Lowell, 649 F.2d at 964 (noting Smith’s

reliance on Chambers). Although rules of evidence often 

exclude testimony that a defendant believes is materially 

favorable or would contribute to raising a reasonable doubt of 

guilt, the Chambers line of cases permits abandoning those

rules when they “infringe upon a weighty interest of the 
37

accused and are arbitrary or disproportionate to the purposes

they are designed to serve.” Holmes v. South Carolina, 547 

U.S. 319, 324 (2006) (alteration and internal quotation marks 

omitted). A weighty interest exists when the Government’s 

decision not to immunize the testimony of a defense witness 

blocks the defendant’s ability to present a meaningful 

defense; that is, with the evidence he might disprove the 

Government’s case, without it he cannot. 

This case requires us to clarify two of our cases 

discussing the clearly exculpatory part of the Smith test. We

have held that a witness’s testimony “undercut” or 

“undermine[d]” by evidence presented by the Government 

was not clearly exculpatory. United States v. Thomas, 357 

F.3d 357, 365–66 (3d Cir. 2004); Mike, 655 F.3d at 172. To 

avoid any misunderstanding as to those terms, we note that 

the obvious purpose of exculpatory evidence is to contradict 

the Government’s evidence against the accused. It is hard to 

imagine a case in which a defendant’s evidence of his 

innocence is not, in some respect, undermined by the 

Government’s evidence of his guilt. The existence of 

conflicting evidence does not affect, however, whether the 

defense evidence is exculpatory, though it may affect its 

weight. Thus, though exculpatory on its own, defense 

evidence that is overwhelmingly undercut or undermined by 

substantial prosecution evidence in the record becomes so 

lacking in credibility that it cannot be clearly exculpatory. 

In this case, Johnson’s testimony is not clearly 

exculpatory. First, we do not know the contents of Johnson’s 

testimony. Quinn offered no proof that Johnson would offer 

exculpatory testimony at all, let alone clearly exculpatory 

evidence. In any event, Johnson’s putative testimony would 
38

be overwhelmed by the evidence of Quinn’s guilt presented 

by the Government. 

Quinn points to Johnson’s statement to police on the 

afternoon of the robbery that Quinn was not involved in the 

robbery. Even if Johnson testified consistently with that 

statement—a matter in doubt—its believability is undermined 

by his additional statement that he did not want to discuss the

involvement of Quinn because the latter is the brother of 

Johnson’s fiancée. Their familial connection provides

Johnson with a reason to shield Quinn from suspicion and 

guilt. Johnson’s credibility would be eroded in other ways as 

well. Johnson had already pled guilty to his role in the bank 

robbery, and thus would have been subject to the accusation 

that any exculpatory testimony was his effort to “take the 

fall” for a friend and codefendant. After his arrest, Johnson 

gave inconsistent statements to the police, first telling them 

that he walked to the shopping center where he met Quinn, 

then reporting that he was driven there by a friend. He also 

told police that he called Quinn from the shopping center 

parking lot, but call records presented at trial showed that no 

calls were made from Johnson’s phone to Quinn. In addition, 

the Government would have attacked Johnson’s credibility by 

presenting evidence of his prior convictions for theft and 

fraud. 

Most important, Johnson’s testimony would be

overwhelmed by the Government’s case against Quinn. He 

called Johnson numerous times on the morning of the 

robbery, and then deleted records of those calls before police 

obtained his phone. He hid his car out of sight of the bank 

while Johnson committed the robbery, and the robbery 

occurred close to Quinn’s relative’s house, where Quinn 
39

drove immediately after Johnson obtained the money. Also,

two of Quinn’s cellmates presented direct evidence that (i) he 

boasted about planning and participating in the robbery and 

(ii) he hoped to get away with the crime by claiming that only 

Johnson was involved. 

This is not an instance where the defense witness’s 

testimony (even assuming it were given as Quinn hopes)

would make suspect the Government’s case. See Smith, 615 

F.2d at 966–67. Considering these items of evidence

together, we cannot conclude that Johnson’s testimony was 

clearly exculpatory. Because Quinn has not made this 

showing, we do not need to consider whether Johnson’s

testimony was essential or whether the Government had a 

strong countervailing interest for refusing to grant Johnson 

immunity. (The latter avoids our scrutinizing the 

Government’s prosecutorial decisions unless necessary to do 

so.)

B. Delay of Johnson’s Sentencing Hearing

We next turn to Quinn’s claim that the Government

engaged in deliberate distortion of the factfinding process by 

delaying Johnson’s sentencing hearing. As mentioned, we 

review for plain error. “If an error is not properly preserved, 

appellate-court authority to remedy the error (by reversing the 

judgment, for example, or ordering a new trial) is strictly 

circumscribed.” Puckett, 556 U.S. at 134. We “correct only 

particularly egregious errors.” United States v. Young, 470 

U.S. 1, 15 (1985) (internal quotation marks omitted). 

We start with whether there is error that is clear. The 

Government’s motion to continue Johnson’s sentencing is not 
40

akin, in either quantity or quality, to the repeated and 

intimidating reminders of criminal exposure imposed on the 

witnesses in Morrison or Webb. Quinn has presented no 

evidence that Johnson intended to testify on Quinn’s behalf 

but was dissuaded from that testimony by the Government’s 

motion. Indeed, Johnson took no position on the delay of his 

sentencing, and informed the Court that he would invoke his 

Fifth Amendment privilege if called to testify, apparently 

without regard to the timing of his sentencing hearing. 

In addition, Quinn typically must “have [his] witness 

available as he finds him.” United States v. Herman, 589 

F.2d 1191, 1199 (3d Cir. 1978). When he first sought 

Johnson’s testimony, Johnson was awaiting sentencing. The 

Government’s motion for continuance merely maintained that 

state of affairs after Quinn’s successful motion to delay his 

trial. Johnson was available to Quinn exactly “as he [found]

him” id., prior to the delay of trial. We discern no distortion 

of the factfinding process, and thus no prosecutorial 

misconduct or error that is clear.

Quinn fares no better on the third and fourth steps of 

our plain error inquiry. He has not demonstrated that 

Johnson’s testimony would have changed the outcome of his 

case or that the absence of this testimony affected the 

integrity, fairness, or public reputation of the judicial 

proceedings here. Even assuming that Johnson would have 

testified that Quinn was uninvolved (which, again, we do not 

know), we are not persuaded, for the reasons explained 

above, that it would have altered the jury’s finding of guilt. 

Quinn had the opportunity to present a full defense against 

the Government charges, including (as he did) by taking the 

stand in his own defense. “The jury had before it all the facts 
41

and claims appellant intended to elicit from the witnesses for 

whom he sought immunity.” United States v. Alessio, 528 

F.2d 1079, 1082 (9th Cir. 1976). We cannot say that Quinn’s 

trial was unfair because it lacked Johnson’s testimony. 

Finally, Quinn also argues, for the first time in his 

Supplemental Brief filed for our rehearing en banc, that the 

District Court erred by finding that Johnson properly invoked 

his Fifth Amendment privilege without requiring that he take 

the stand and invoke the privilege as to specific questions. 

Because this issue was not raised in Quinn’s notice of appeal 

or opening brief, it is waived. Fed. R. App. P. 28(a)(5);

United States v. Hoffecker, 530 F.3d 137, 162 (3d Cir. 2008);

Kost v. Kozakiewicz, 1 F.3d 176, 182 & n.3 (3d Cir. 1993). 

Even if it were not, Quinn acknowledges there is no plain 

error here, Appellant’s Supplemental Br. at 23 n.16, as he

does not challenge Johnson’s right to claim the privilege.

V. Conclusion

The prosecutorial misconduct test from our pre-Smith 

cases—deliberate intent to distort the factfinding process—

provides a due process guard against Government 

interference with a defense witness. The Smith five-part test 

aids in this analysis when the Government exercises its 

statutory authority not to immunize a witness for the defense.

Our holding today departs from Smith, however, by 

eliminating the grant of a judicially imposed remedy of use 

immunity to a defense witness. Courts lack that authority, as 

immunity is a statutory creation reserved to the Executive 

Branch. If the accused can show a due process violation, a 

trial court has the authority to vacate a conviction to allow a 
42

new trial where the Government may immunize the witness’s 

testimony or, if the Government won’t immunize, to dismiss 

the charges. 

Applying our revision to this case, Quinn fails to show 

that the Government interfered unconstitutionally with 

Johnson’s decision not to testify. We thus affirm.