In a majority opinion authored by Justice William J. Brennan, Jr., the Court held that criminal defendants could bring claims that evidence against them was obtained in violation of the Fourth Amendment to the United States Constitution in a collateral attack under the federal habeas corpus statute.

The Supreme Court's decision in Kaufman also ran counter to most other previous decisions by federal appeals courts, most of which had held that claims of unreasonable searches and seizures could only be raised on direct appeal, rather than in collateral proceedings.

[1] The decision in Kaufman also applied the "deliberate bypass" standard the Supreme Court had outlined in its 1963 decision in Fay v. Noia, in which the Court had held that state prisoners were permitted to raise claims in federal habeas proceedings so long as they did not "deliberately bypass" the procedures for raising such claims in state court.

[2] Kaufman has since been described as "the last important case of the 1960s to defend a liberal interpretation of habeas corpus on the grounds of Fay".

In part on the basis of Justice Hugo Black's dissent in Kaufman, the Supreme Court went on to significantly limit the availability of habeas corpus relief in the 1976 case Stone v.