U.S. Supreme Court Cases Involving Prosecutorial Misconduct:


1959 – Napue v. Illinois
The principal state witness in a murder trial was asked by an Assistant District Attorney whether he had received consideration in exchange for his testimony. The witness said that he had not. The ADA knew this to be false but did not reveal it. The U.S. Supreme Court held that the due process clause of the Fourteenth Amendment bars prosecutors from presenting false testimony and requires 
1963 – Brady v. Maryland
Petitioner and a companion were both convicted of first-degree murder and sentenced to death. The companion made a series of statements, one of which indicated that it was he, and not the petitioner, who actually committed the murder. Prosecutors turned over all of the companion’s statements except the one that exculpated the petitioner. In Brady v. Maryland, the U.S. Supreme Court held that suppression of evidence favorable to the accused by the prosecution violates due process where the evidence is material either to guilt or to punishment, irrespective of the good faith or bad faith of the prosecution.
1972 – Giglio v. United States
A key witness against Petitioner testified at trial that he had not received a promise for leniency from the state in return for his testimony. Unbeknownst to the trial prosecutor, the witness had in fact received a promise for leniency from another prosecutor in the office. Petitioner discovered this and filed a motion for a new trial. The U.S. Supreme Court held that the prosecution was obligated to disclose to the defense any promise or expectation of leniency it offered to a witness. It clarified that the state’s Brady obligation extends to all prosecutors in the office, and that it is up to such offices to create systems to ensure that such information is disclosed. Further, the Court clarified that impeachment evidence – evidence affecting the credibility of a witness – is Brady material and must be disclosed.
1976 – United States v. Agurs
Petitioner was convicted of murder after a trial in which he argued he had acted in self-defense. Subsequently petitioner sought a new trial because the state had failed to disclose the victim’s criminal record. The U.S. Supreme Court held that there was little difference between a general request by defense counsel for Brady material and the absence of a request altogether, and it found that prosecutors are obligated to turn over exculpatory evidence whether or not defense counsel asks for it.
1985 – United States v. Bagley
Respondent was indicted on firearms and narcotics charges. Prior to trial, he requested that the prosecution disclose any “deals, promises, or inducements” made to witnesses in exchange for their testimony. The prosecution did not disclose that its two principal witnesses worked with the Bureau of Alcohol, Tobacco, and Firearms (ATF) in an undercover investigation of respondent. Respondent sought a new trial under Brady v. Maryland. The U.S. Supreme Court again held that Brady requires disclosure of impeachment evidence. It also clarified the “materiality” prong of Brady. It said that a Brady violation occurs if the withheld evidence was “material” in the sense that there was a “reasonable probability” that its disclosure would have led to a different result in trial or sentencing. It explained that “reasonable probability,” meant “a probability sufficient to undermine confidence in the outcome.”
1995 – Kyles v. Whitley
Petitioner was convicted of first-degree murder and sentenced to death. Prior to trial, police had collected eyewitness statements containing physical descriptions of the attacker which were inconsistent with characteristics of the petitioner. These statements were not disclosed to the defense. Post-trial petitioner argued that this evidence had been suppressed in violation of Brady v. Maryland. The U.S. Supreme Court agreed. It imposed an affirmative duty on prosecutors to become aware of and disclose any favorable evidence held by others acting on the government’s behalf, including the police. The Court also clarified the materiality standard. It said that a defendant is not required to show that had the withheld evidence been disclosed, more likely than not he would have been acquitted. It reiterated that instead, a defendant need only show that the undisclosed evidence “undermines confidence” in the trial outcome.
2004 – Banks v. Dretke
Petitioner was convicted of murder and sentenced to death. The state represented that it had disclosed all Brady material, but it nevertheless failed to disclose the fact that a key witness was a paid government informant and that another witness’s testimony had been coached. Furthermore, prosecutors failed to correct the record when these witnesses testified falsely. Petitioner sought relief because of the apparent Brady violation but lost in the U.S. Court of Appeals for the 5th Circuit.  The U.S. Supreme Court held that the lower court had erred in dismissing Petitioner’s Brady claim. It placed the onus for Brady compliance clearly on prosecutors. It said defendants need not “scavenge for hints of undisclosed Bradymaterial” and “[a] rule . . . declaring ‘prosecutor may hide, defendant must seek’ is not tenable.” The Court also reiterated the holding in Kyles v. Whitley: “the materiality standard for Brady claims is met when ‘the favorable evidence could reasonably be taken to… undermine confidence in the verdict.'” When police or prosecutors conceal exculpatory material in the state’s possession, it is incumbent on the state to set the record straight.

Murder Conviction Reconsidered when DA Withholds Evidence

Jesse Gonzalez was convicted of first degree murder with special circumstances for killing a police officer on duty.  The conviction arose after he used a shotgun when Los Angeles Sheriff’s Department Deputies kicked down his front door while serving a search warrant.  

Gonzalez’s defense was self-defense.  He further testified at trial that he never heard the officers announce who they were or that they had a warrant.  Gonzalez thought the officers were members of a rival gang, the Bassetts, coming to kill him and his cousin.

Thus, the key issue at trial was the credibility of Gonzalez’s professed intent, as it was determinative of whether he understood who was outside his door as he armed himself with the shotgun and then blasted the officers entering his home.

The prosecution argued that Gonzalez knew in advance the police were coming and that he planned on using the raid to “bag a cop.”  This theory was entirely based on the testimony of William Acker, a prisoner who shared the same cell as Gonzalez.  Acker testified at trial that Gonzalez told him he even planned in advance to say he mistook the officers for members of the Bassett gang.

At trial, Gonzalez’s attorneys attempted to impeach Acker, who had previously pled guilty to murder, but the jury did convict Gonzalez.  During the penalty phase of the trial, the death penalty was imposed.

While Gonzalez’s case was pending, however, a scandal erupted in the news regarding false testimony by jailhouse informants.  While Acker was not a jailhouse informant, Gonzalez’s attorneys were nevertheless keen on receiving prosecution documents concerning Acker’s credibility.  The District Attorney resisted the discovery requests and, meanwhile, Gonzalez’s trial continued and he was convicted.  

In Gonzalez’s appeal, he alleged ineffective assistance of counsel for his counsel failing to receive impeachment materials concerning Acker (even though Gonzalez conceded he did not know if it existed at all), among a long list of other failures.  Gonzalez pointed out, for example, that he had worked a full day before the police served the warrant, which seemed to contradict Acker’s testimony that Gonzalez waited for the police in the hopes of “bagging a cop.”  Gonzalez claimed that his attorney should have made this argument.

Perhaps more significantly, Gonzalez also alleged prosecutorial misconduct for not turning over impeachment materials concerning Acker.  Gonzalez argued that the material surely must exist if the prosecution refused to cooperate.

In the course of the appeal, the prosecution then produced six psychological reports showing Acker had a “severe psychological disorder” – the impeachment material Gonzalez could have used during trial.  The reports said Acker repeatedly lied and faked suicides to attempt transfers between jails.  Gonzalez knew that Acker had told him he again wanted a transfer from the jail he and Gonzalez were at together.

Based on this, Gonzalez amended his appeal and the Ninth Circuit Court of Appeals, in Gonzalez v. Wong (warden of California State Prison), 2011 DJDAR 17552, agreed with Gonzalez.  Citing toBrady v. Maryland (1963) 373 U.S. 83, a landmark United States Supreme Court case concerning the duty of a prosecutor to disclose information, the Ninth Circuit found that the prosecution’s withholding of such reports unduly prejudiced Gonzalez’s right to a fair trial.  The Ninth Circuit went so far as to comment that such reports “could have affected” the jury’s opinion of Acker’s credibility.

The case was remanded to the lower court for further proceedings consistent with the Ninth Circuit’s ruling.  The conviction was not reversed or set aside, but Mr. Gonzalez was certainly given hope that his self-defense claim could be found more credible.