Case Citator › Ker v. California

Ker v. California

Is it still good law? What later courts have actually done to this case.

Questioned by some courts
Court
Supreme Court of the United States
Citation
374 U.S. 23
Decided
Confirmed treatments
1
Flagged citations read
141 of 141
Citing cases (total)
141
Treatment dates
2025
Questioned by some courts
At least one reviewed court has questioned this case’s reasoning or continued validity. No reviewed court has overruled it. Ker v. California is questioned on its rule tying the lawfulness of arrests for federal offenses to state law. In United States v. Steinman, the Ninth Circuit said the Supreme Court has moved away from that rule and found it of limited use for the question before it.
More on how this was screened

That treatment is listed below. All 141 flagged citations have been read; the other opinions did not establish an adverse treatment of Ker.

Every treatment on this page is written from the citing opinion itself, with a verbatim quote, never copied from a commercial citator. A citation flagged by our screen but not shown here was read and found not to weaken this case.

141 later cases cite Ker v. California; 141 of those citations sat close to treatment language and were flagged for reading, and all of them have been read. Citations that did not sit near treatment language were not flagged and were not read one by one, so a court that weakened this case without using any of that language would not appear here.

Relying on Ker v. California?

This page shows what later courts did to it. Ask about your specific facts and see whether it still carries your argument, with citations you can check.

Treatments

Questioned

  • The Ninth Circuit questioned Ker's state-law rule for arrests involving federal offenses, finding it of limited use after later Supreme Court authority.

    United States v. Steinman · Ninth Circuit · filed

    We are also unpersuaded by the district court’s reliance on Ker v. California, 374 U.S. 23 (1963). To be sure, the Ker court stated that “the lawfulness of arrests for federal offenses is to be determined by reference to state law insofar as it is not violative of the Federal Constitution.” Id. at 37. But the Supreme Court has moved away from this rule, see Moore, 553 U.S. at 172–73, and we find it to be of limited use in resolving the cross-enforcement issue.
    Read the full opinion on CourtListener →

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