Appellants were indicted and convicted on charges stemming from a prison escape incident. On appeal they challenge the trial court’s rulings on a number of matters, including several pretrial and post-trial motions. We affirm.
I
Lawrence Caldwell, Albert Garza, and Howard Zumberge were inmates of the federal penitentiary in Marion, Illinois. On February 14,1979, under cover of thick fog, the trio attempted to escape from the institution by scaling its fences. Caldwell failed and was apprehended atop the inner perimeter fence; Garza and Zumberge succeeded and remained at large for several days. State and federal law enforcement officers finally captured Garza, after a brief gun battle, in a church basement. Zumberge was hiding in the same church but surrendered more peacefully. Zumberge was taken into custody and Garza was hospitalized for a gunshot wound.
All three were indicted on March 28, 1979. At trial, appellants elected to represent themselves pro se, although appointed counsel was available. They were acquitted on three counts and found guilty on the remaining counts.
II
Appellants’ initial contentions concern adverse pretrial publicity which they claim prejudiced the jury. Due process, of course, requires that an accused be tried by an impartial jury free from outside influences.
Maxwell v. Sheppard,
*139 After conducting our own independent review and evaluation of the trial court’s voir dire examination, we perceive no actual prejudice arising from pretrial publicity. Although the record reveals that many potential jurors were familiar with the case, Judge Foreman’s careful questioning and close scrutiny filtered out the biased veniremen. 2 Of those selected, only four jurors had read or heard of the case, and none possessed more than passing familiarity with the escape. 3 Under the circumstances, we cannot say the district court abused its discretion by its approach to the pretrial publicity problem.
Reflecting the same concern, appellants sought a change of venue as well as additional peremptory challenges and challenges for cause, all of which were denied. Appellants, of course, claim these denials were erroneous. We disagree. As to the change of venue motion, the governing authority is rule 21(a), Fed.R.Crim.P., which provides, in part, that
[t]he court upon motion of the defendant shall transfer the proceeding as to him to another district ... if the court is satisfied that there exists in the district where the prosecution is pending so great a prejudice against the defendant that he cannot obtain a fair and impartial trial at any place fixed by law for holding court in that district.
Granting or denying a change of venue motion is within the trial court’s discretion.
*140
United States v. Lamb,
Appellants’ claims concerning additional juror challenges, predicated on supposed widespread, prejudicial publicity, are equally unfounded. As we have noted, there was some publicity, but it was hardly so inflammatory and prejudicial as to require any remedy beyond the measures taken by Judge Foreman. 4 Appellants contend that jurors Reed, Barham, Parker, and Waldron should have been excused for cause and that it was error to allow them on the jury. We disagree. The record shows that Reed read about the case and hunted in the area where Garza and Zumberge were captured, but could not recall any specifics. Barham, as we have demonstrated elsewhere, 5 only vaguely recollected the escape and, frankly, seemed more interested in the dogs used to track the appellants than in the appellants themselves. Parker merely had served as a juror on an unrelated murder case. Finally, Waldron's husband had been a prison guard in a state facility roughly sixteen years ago. Although from appellants’ standpoint such jurors may not have been optimal, their presence did not constitute an abuse of discretion since each indicated that he or she could render an impartial verdict based upon the evidence.
We dispatch appellants’ argument regarding additional peremptory challenges with the observation that such challenges are limited partly because they serve as a tactical tool of defense counsel seeking one biased juror almost as often as they serve to promote fair trials.
See Jeffers v. United States,
II
Appellants next question certain evidentiary rulings which they claim prevented them from presenting a defense. At trial, appellants admitted they escaped, or attempted to escape, 6 so the sole issue became whether they were compelled to do so by prison conditions. They hoped to prove their defense of duress or necessity 7 by presenting witnesses who would testify, in effect, that violence between inmate factions, as well as appellants’ attempts at negotiations between these factions, endangered appellants’ lives, and that inadequate medical treatment was damaging appellant *141 Caldwell’s eyesight. In particular, appellants sought to subpoena twelve inmates from various correctional facilities across the country to testify about the threat warring factions within Marion penitentiary posed to appellants. Judge Foreman, however, only allowed appellants to subpoena seven inmates, all housed at Marion. In his opinion, the other five witnesses’ testimony would have been cumulative and their presence would have required unnecessary transportation expenses and delay.
We recognize that rule 17(b), Fed.R.Crim.P., requires a court to subpoena witnesses for indigent defendants, but only where “the presence of the witnesses is necessary to an adequate defense.” In deciding whether a rule 17(b) subpoena should issue the trial judge has wide discretion.
United States v. Micklus,
Appellants also challenge the trial judge’s exclusion of certain defense evidence which he deemed irrelevant. They sought to introduce testimony concerning two murders that occurred approximately three months before the escape, attempting to link the murders with their fear of harm and resulting compulsion to flée the prison. We believe the evidence was properly excluded. Even if we assume the circumstances surrounding the murders were somehow relevant to appellants’ case, such evidence still could be excluded
if its probative value [was] substantially outweighed by the danger of unfair prejudice, confusion of the issues, or misleading the jury, or by considerations of undue delay, waste of time, or needless presentation of cumulative evidence.
Fed.R.Evid. 403. The significant delay between the murders and the escape, by itself, suggests the limited probative value of the murder evidence. Quite apart from its doubtful probativeness, such evidence would have necessitated a trial within a trial just to prove certain inmates harmed others and now sought to harm appellants. Other defense witnesses already had established that appellants were in danger. Evidence of the murders probably would have confused the jurors and, in any event, was clearly cumulative. Appellants have failed to show an abuse of discretion here.
Harris v. Harvey,
Ill
Appellants complain that the trial court failed to instruct the jury on their defense of duress, erroneously replacing it with the defense of coercion instead. In our view, the substituted instruction benefited appellants. Under the duress defense recently announced by the Supreme Court in
United States v. Bailey,
IV
The fourth major argument pressed by appellants claims an equal protection violation because the Marion penitentiary’s law library lacked sufficient resources for them to use in preparing an adequate defense. In
Bounds v. Smith,
V
Appellant Caldwell attacks the district court’s refusal to sever his trial from that of Garza and Zumberge. He claims, in essence, that he was prejudiced by the joint trial because he did not commit the same crime and, in particular, did not shoot any law enforcement officers. Severance rulings are committed to the trial judge’s discretion and are not disturbed on appeal absent abuse,
United States v. Hedman,
In deciding whether to allow joinder of different defendants in a single trial we must balance the government’s benefit in jointly trying related incidents
*143
and defendants against the prejudice to a defendant of possibly having multiple offenses and participants confused with each other.
United States v. Luna,
The Supreme Court has expressly refused to fashion a “hard-and-fast formula that, when a conspiracy count fails, joinder is error as a matter of law.”
Schaffer v. United States,
VI
We now turn to the last argument, that Garza’s pretrial motion to suppress certain government evidence should have been granted. While in the hospital awaiting treatment for his gunshot wound, Garza was approached by a state laboratory examiner and Special Agent Donald Jones of the Federal Bureau of Investigation. The examiner was present to apply a chemical substance to Garza’s hands to determine which hand fired the gun during the church basement gun battle. Just before the chemical application commenced, according to Agent Jones’ testimony, Garza turned to Jones and asked what the examiner was doing in the emergency room. Jones responded that “[h]e’s going to run a test on your hands to see which hand you used to fire the gun when you shot the sheriff.” At first Garza turned away without comment, but as the examiner began applying the solution to Garza’s hand Garza suddenly turned to Jones and stated, without provocation, that it was the right hand. Jones then asked if Garza was right-handed or left-handed, to which Garza responded “both.” The examiner continued applying the solution and Garza once again turned to Jones and said, “he doesn’t have to do that. I told you it was the right hand.” Tr. at 310.
Since
Miranda v. Arizona,
VII
For the foregoing reasons, appellants’ convictions are
AFFIRMED.
Notes
. Prejudice is presumed in rare cases where pretrial publicity is pervasive and inflammatory. See, e.
g., Maxwell v. Sheppard,
. To insure impartiality, Judge Foreman took the following steps: (1) initially determined the extent of media exposure to the venire panel; (2) individually questioned, out of the presence of the others, each exposed venireman; (3) extensively questioned each as to the extent and degree of publicity to which he was exposed; (4) elicited responses as to the partiality or impartiality of the venireman due to the publicity; and (5) excused for cause eleven veniremen who were opinionated.
. Juror Barham’s responses to Judge Foreman’s questions illustrate the harmless, vague impressions held by the few jurors exposed to pretrial publicity.
The Court: Mr. Barham, where did you hear or read about this case before coming here today?
Mr. Barham: Read it in the Southern Illinoisian newspaper.
The Court: When did you do that, sir?
Mr. Barham: Right after it happened, I suppose. I don’t remember the exact dates of it.
The Court: Did you read about it only the one time?
Mr. Barham: Seemed like there was two different articles, two or three different days.
The Court: Is that the only other time you have heard or read about it?
Mr. Barham: I heard them talk about it at the mines — some people that live down there — that area.
The Court: Did they purport to know something about the facts of the case or was it just conversation?
Mr. Barham: More or less just conversation and talk.
The Court: Did any of them purport to know anything about the facts of the case?
Mr. Barham: Well, I can’t honestly say that they were talking facts. They were just talking in particular about the dogs they had and what not.
The Court: Would what you heard or read about, and here [sic] at this minute, would that tend to influence you in favor of these defendants or against these defendants or for or against the Government, Mr. Barham?
Mr. Barham: No sir, I don’t think so.
The Court: Could you set that aside and reach a fair and impartial verdict in this case, based on what goes on only in this courtroom?
Mr. Barham: I think so.
The Court: Could you?
Mr. Barham: Yes, sir.
The Court: You understand that’s what our aim is here, to get fair and impartial jurors, ones that will listen to only the evidence here in the courtroom totally uninfluenced by any other matters that they may have heard about this case?
Mr. Barham: Yes, sir.
The Court: You think you could do that?
Mr. Barham: I think I can, yes, sir.
Tr. of Jury Selection, at 108-09.
. See note 2, supra.
. See note 3, supra.
. Caldwell did not escape but admitted his attempt to do so.
. Although appellants did not distinguish duress from necessity, the Supreme Court recently noted the common law distinction between the two:
Duress was said to excuse criminal conduct where the actor was under an unlawful threat of imminent death or serious bodily injury, which threat caused the actor to engage in conduct violating the literal terms of the criminal law. While the defense of duress covered the situation where the coercion had its source in the actions of other human beings, the defense of necessity, or choice of evils, traditionally covered the situation where physical forces beyond the actor’s control rendered illegal conduct the lesser of two evils.
United States v. Bailey,
. Although appellants characterize the conspiracy count as “improper,” we will assume for purposes of our discussion that appellants intended to charge the government with bad faith.
