Glasser v. United States, 315 U.S. 60 (1942), was a landmark decision of the US Supreme Court on two issues of constitutional criminal procedure.

Glasser was the first Supreme Court decision to hold that the Assistance of Counsel Clause of the Sixth Amendment required the reversal of a criminal defendant's conviction if his lawyer's representation of him was limited by a conflict of interest.

[5] All of the Court's prior jury pool discrimination cases had involved the exclusion of African-Americans and been litigated under the Fourteenth Amendment's Equal Protection Clause.

"[6] Daniel D. Glasser and Norton I. Kretske were Assistant United States Attorneys in the Northern District of Illinois, specializing in liquor and revenue offenses.

[11] The trial began on February 6, 1940 before Judge Patrick Thomas Stone, of the Western District of Wisconsin, sitting by designation.

[13] Another prosecution witness, illegal distillery landlord William F. Workman, testified that Capone-affiliated Louis Schiavone had posted approximately $1,000,000 in bail bonds.

"[14] Still another, Walter Kwiatkowski, testified that he paid Horton $600 (in addition to the $200 bond) to have the case against him dropped where Glasser was acting as prosecutor.

[16] Mae and Anthony Jurkas, two small-time bootleggers, testified that Glasser declined to prosecute them in exchange for the name of their bootlegging boss.

[18] Alexander Campbell, an Assistant U.S. Attorney from Indiana testified that Roth had offered him a bribe in a bootlegging case, saying: "That's the way we handle things in Chicago.

"[18] The government's final witness, alcohol tax investigator Thomas Bailey, testified that Glasser had repeatedly delayed a grand jury in a case he was involved with.

[23] Stewart and George Callaghan closed for Glasser and Kretske; Hess for Kaplan; Cassius Poust for Roth; Ward concluded the government's argument.

[27] Revenue department special intelligence agent Clarence L. Converse had observed the entire trial with an eye towards a follow-on tax prosecution.

"[31] The defendants argued: (1) that the indictment should have been quashed because of the absence of women from the grand jury;[31] (2) that the indictment was not returned in open court;[32] (3) that the indictment was duplicitous, inconsistent, and vague;[33] (4) that there was insufficient evidence to support the verdict;[34] (5) that the trial judge should have granted a continuance, rather than appoint Stewart to represent Kretske;[35] (6) that Roth should have been severed from the other defendants;[36] (7) that the reports of the Alcohol Tax Unit were hearsay;[36] (7) that the two government exhibits not admitted into evidence were sent to the jury during its deliberations;[36] (8) that Glasser had been cross-examined on matters not pertinent to the charge and not within the scope of his direct examination;[37] (9) that the cross-examination of U.S. Attorney Campbell had been unduly restricted;[37] (10) that evidence beyond the scope of the bill of particulars had been introduced;[37] (11) that there was insufficient corroboration of the accomplice testimony against Kretske;[38] (12) that certain testimony of Alexander Campbell was erroneously admitted;[39] (13) that the admission of various prejudicial evidence had the cumulative effect of denying the defendants a fair trial;[40] (14) that the trial judge's cross-examination of witnesses and other comments crossed the line into advocacy;[41] and (15) that the trial judge should have granted a new trial because of the exclusion of women from the jury pool.

[42] Former United States Attorney General Homer S. Cummings petitioned the Supreme Court for certiorari, which was granted on April 7, 1941.

To determine the precise degree of prejudice sustained by Glasser as a result of the court's appointment of Stewart as counsel for Kretske is at once difficult and unnecessary.

The right to have the assistance of counsel is too fundamental and absolute to allow courts to indulge in nice calculations as to the amount of prejudice arising from its denial.

[61]The Court further held that: "The deliberate selection of jurors from the membership of particular private organizations definitely does not conform to the traditional requirements of jury trial.

[62] The court rejected the defendant's other arguments: (1) that women were improperly excluded from the grand jury under Illinois law (as incorporated by federal jury selection law at the time);[63] (2) that the indictment was not returned in open court because the notation indicating that the indictment was returned in open court was added after the fact;[64] (3) that the indictment was insufficiently definite;[65] (4) that the evidence was insufficient to sustain the conviction;[66] (5) that the admission of certain evidence was prejudicial;[67] and (6) that the trial judge's own questioning of certain witnesses and limitations on cross-examination were prejudicial.

[69] They argued that Glasser had acquiesced to the appointment by his silence, especially in light of his years of experience as a federal criminal prosecutor, and had failed to preserve the error by not objecting.

[49] Further, the dissent argued that the joint representation was beneficial: A conspiracy trial presents complicated questions of strategy for the defense.

[73] Judge F. Ryan Duffy, of the Eastern District of Wisconsin, sitting by designation, denied a government motion to dismiss Kretske's habeas petition on April 14 and set a hearing for the following day.

"[78] The Court continued to deal with this issue in Dukes v. Warden (1972), Holloway v. Arkansas (1978), Cuyler v. Sullivan (1980), Burger v. Kemp (1987), Wheat v. United States (1988), and Mickens v. Taylor (2002).

Thus, a defendant who shows that a conflict of interest actually affected the adequacy of his representation need not demonstrate prejudice in order to obtain relief.

But until a defendant shows that his counsel actively represented conflicting interests, he has not established the constitutional predicate for his claim of ineffective assistance.

[80] Glasser is the first majority opinion of the Court to use the phrase "cross-section of the community,"[1][2] and the first jury discrimination case to invoke the Sixth Amendment (rather than equal protection).

[3]The Supreme Court would eventually reverse criminal convictions due to the exclusion of women from the jury pool in Taylor v. Louisiana (1975) and Duren v. Missouri (1979).

The fair cross-section requirement was extended to civil cases in Thiel v. Southern Pacific Co. (1946), where wage earners had been excluded from the jury pool.