(a) When judicial notice shall be taken without request. Every court shall take judicial notice without request of the common law, constitutions and public statutes of the United States and of every state, territory and jurisdiction of the United States and of the official compilation of codes, rules and regulations of the state except those that relate solely to the organization or internal management of an agency of the state and of all local laws and county acts.
R 4511.Judicial notice of law.
Article 45. Evidence · Last amended 2019 · Last verified July 21, 2026
In one sentenceCPLR 4511 tells New York courts which laws they must notice on their own, which they may notice or must notice on request, and how the judge, not the jury, determines and reviews questions of foreign or sister-state law.
Full Text of CPLR 4511
(b) When judicial notice may be taken without request; when it shall be taken on request. Every court may take judicial notice without request of private acts and resolutions of the congress of the United States and of the legislature of the state; ordinances and regulations of officers, agencies or governmental subdivisions of the state or of the United States; and the laws of foreign countries or their political subdivisions. Judicial notice shall be taken of matters specified in this subdivision if a party requests it, furnishes the court sufficient information to enable it to comply with the request, and has given each adverse party notice of his intention to request it. Notice shall be given in the pleadings or prior to the presentation of any evidence at the trial, but a court may require or permit other notice.
(c) Determination by court; review as matter of law. Whether a matter is judicially noticed or proof is taken, every matter specified in this section shall be determined by the judge or referee, and included in his or her findings or charged to the jury. Such findings or charge shall be subject to review on appeal as a finding or charge on a matter of law.
(d) Evidence to be received on matter to be judicially noticed. In considering whether a matter of law should be judicially noticed and in determining the matter of law to be judicially noticed, the court may consider any testimony, document, information or argument on the subject, whether offered by a party or discovered through its own research. Whether or not judicial notice is taken, a printed copy of a statute or other written law or a proclamation, edict, decree or ordinance by an executive contained in a book or publication, purporting to have been published by a government or commonly admitted as evidence of the existing law in the judicial tribunals of the jurisdiction where it is in force, is prima facie evidence of such law and the unwritten or common law of a jurisdiction may be proved by witnesses or printed reports of cases of the courts of the jurisdiction.
Plain-English Summary
CPLR 4511(a) requires every court to take judicial notice, without anyone asking, of the common law, constitutions, and public statutes of the United States and of every state and territory, along with New York's official compilation of codes, rules, and regulations, except portions dealing only with an agency's internal management, and all local laws and county acts. A lawyer never needs to prove this body of law through witnesses or documents; the court is presumed to know it.
Subdivision (b) covers a second, more discretionary tier: private acts and resolutions of Congress or the state legislature, local ordinances and regulations, and the laws of foreign countries. A court may notice these on its own, but must notice them if a party asks, supplies enough information for the court to comply, and gives adverse parties notice of the request, typically through the pleadings or before evidence comes in at trial.
Subdivisions (c) and (d) fix who decides and what the court can look at. Whether by notice or proof, the question of what a law says belongs to the judge or referee, not the jury, and that determination is reviewable on appeal as a matter of law. In reaching it, the court can weigh testimony, documents, or argument from any source, whether a party offered it or the court found it independently, and a printed statute from an official government publication counts as prima facie evidence of what the law is.
Frequently Asked Questions
Does a lawyer have to prove what the law is in New York courts?
Not for New York's own common law, constitutions, and public statutes, or those of the United States and other states; CPLR 4511(a) requires courts to notice that law automatically.
Does a court have to notice a foreign country's law?
Only if a party requests it, provides enough information for the court to comply, and gives adverse parties notice; otherwise it is discretionary under CPLR 4511(b).
Who decides what a foreign or sister-state law says, the judge or the jury?
The judge or referee. CPLR 4511(c) makes the determination of any such matter of law reviewable on appeal as a question of law, not a jury finding.
Can a court research foreign law on its own?
Yes. CPLR 4511(d) lets the court consider testimony, documents, or argument on the point whether a party offered it or the court found it through its own research.
Is a printed copy of a statute good evidence of the law?
Yes. A printed statute or similar publication, commonly recognized as evidence of the law in that jurisdiction's own courts, is prima facie evidence of what the law provides.
Advisory Committee Notes
This rule represents an expansion of CPA § 344-a which permitted, but did not require, the court to take judicial notice of the law of other states, private acts of this state or of Congress, ordinances, resolutions, by-laws or proceedings of governing bodies of municipalities of this state, and rules or regulations of various executive departments, boards and officers of this state and its subdivisions and of the United States.
Discretion to refuse to take judicial notice of the law of sister-states seems clearly unwarranted. Cf. Pfleuger v Pfleuger, 304 NY 148, 152, 106 NE2d 495, 496–97 (1952). The law of other states is determinable almost as easily as the law of the United States and every lawyer should be capable of finding it. Twenty-six states and territories have adopted section 1 of the Uniform Judicial Notice of Foreign Law Act which provides, “Every court of this state shall take judicial notice of the common law and statutes of every state, territory and other jurisdiction of the United States.” Other states, while not adopting the uniform rule have, in this respect, followed it. See the statutes collected in Morgan, Maguire & Weinstein, Cases and Materials on Evidence 52–55 (1957); see also Uniform Rules of Evidence, Rule 9.
The discretionary nature of the former New York statute created a serious dilemma for the careful lawyer who must have assumed that the court would not exercise its discretion to take judicial notice. This meant that he would have to come to court prepared to prove the law of a sister-state, observing all the rules of evidence applicable to proof of facts. This rule follows the Uniform Judicial Notice of Foreign Law Act and the Uniform Rules of Evidence in providing that the common law and public statutes of states, territories and other jurisdictions of the United States shall be judicially noticed.
This rule, however, does not require the judge to take judicial notice of private acts and resolutions, ordinances and regulations of political subdivisions and the laws of foreign countries, since the judge may not be aware of the existence of such laws and regulations; moreover, they may not be readily available to him. Insofar as he has discretion to notice them the former law is unchanged. If, however, a litigant requests the judge to take judicial notice and furnishes him with sufficient information to reach a decision, he must take judicial notice. The phrase “ordinance, resolution, by-law, rule or proceeding” of the former statute is encompassed by “ordinances and regulations” of this rule. Similarly, “governmental subdivisions” covers the former terms “city, county, town or village” and “officers” and “agencies” includes “public board, agency or officer.” Under both CPA § 344-a and § 3 of the Uniform Judicial Notice of Foreign Law Act the common law had been changed so that the question of what constitutes the law was one for the judge and not for the jury. Thus, the only effect of the judge’s failure to take judicial notice was that he bound himself to observe the rules of evidence in reaching a conclusion on matters of foreign law. He might not have then read a law review article or treatise on the point, but must have obtained his information from public decisions, statutes and from expert testimony heard in open court. Under this rule, the judge, if he is unfamiliar with the legal system of a foreign country, could require experts on foreign law to testify and be cross-examined. This is the same discretion given to him under former § 344-a. If the parties fail to submit testimony required by him, the judge need only find, in the words of this rule, that there has not been “sufficient information to enable . . . [him] to comply with the request.” Cf. Wagner v Derecktor, 306 NY 386, 391–92, 118 NE2d 570, 573 (1954). In contrast to the former uncontrolled discretion, a standard is provided by this rule to guide both judge and attorneys in determining when judicial notice should be taken.
It is apparent that in any litigation of substance, attorneys will seek out foreign law experts both as advisors to themselves and in order to insure that the court will properly evaluate their position. Nevertheless, there are many cases in New York involving small sums or nonaffluent parties where it is important that expenses be minimized if justice is to be done. See Nussbaum, Proof of Foreign Law in New York: A Proposed Amendment, 57 Colum L Rev 348 (1957). This rule better accomplishes this purpose than did the former statute.
That portion of subd (a) of this rule from “and of the official compilation” to “an agency of the state” refers practitioners and the courts to the official compilation provided for by §§ 102–105 of the Executive Law and conforms to § 106 of that law regarding the proof of any code, rule or regulation contained in such compilation. The last eight words of subd (a) replace certain provisions in the Consolidated Laws that have been repealed. See former County Law § 307; former Optional County Government Law, §§ 301(13), 1143, 1209(13), 1252.
The last sentence in subd (b), dealing with notice, is taken from rule 9 of the Uniform Rules. See Committee on the Revision of the Law of Evidence, Report to the Supreme Court of New Jersey 20 (May 25, 1955). Subd (b) replaces paragraph D of former § 344-a. The former law implicitly required pleading but permitted the court to waive the requirement. Cf. Greiner v Freund, 386 App Div 996, 997, 144 NYS2d 766, 767 (1st Dept 1955). The notice requirement under this rule may be waived by the judge since subd (b) gives him power to take judicial notice without request and, therefore, without notice. Subd (c) and (d) are the same as paragraphs B and C of former § 344-a, respectively, with minor language changes.
In view of the breadth of this provision, former § 380-a, which dealt with proof of rules, orders or regulations of the New York State war council, and § 381, which dealt with proof of colonial statutes, have been omitted as unnecessary. Judicial notice should be taken of these orders, regulations and statutes.
While this rule is essentially the same as that recommended by the California Law Revision Commission (Recommendation and Study Relating to Judicial Notice of the Law of Foreign Countries I-9 (Feb. 1, 1957)), the advisory committee decided not to adopt the following recommendation of that Commission: If a court is unable to determine what the law of a foreign country or a political subdivision of a foreign country is, the court may, as the ends of justice require, either apply the law of this State if it can do so consistently with the Constitution of this State and of the United States or dismiss the action without prejudice.
This proposal has merit, but the problem seems, at this time, best left for solution through case law development. Cf., e. g., Leary v Gledhill, 8 NJ 260, 84 A2d 725 (1951).
Editor's Notes Laws 2019, ch 223, § 3, eff December 28, 2018, provides:
§ 3. This act shall take effect on the same date and in the same manner as a chapter of the laws of 2018, amending the civil practice law and rules relating to judicial notice of an image, map, location, distance, calculation, or other information taken from a web mapping service, as proposed in legislative bills numbers S. 9061 and A. 11191, takes effect.
Amendment History
Add, L 1962, ch 308; amd, L 1962, ch 315, § 1, eff Sept 1, 1963; L 2018, ch 516, § 1, effective December 28, 2018; L 2019, ch 223, § 1, effective December 28, 2018.
Source & verification. Provision text, History, and Advisory
Committee Notes are reproduced verbatim from the Consolidated Laws of New York.
Last verified July 21, 2026.
· Official source
Also known as: judicial notice of law New Yorkjudicial notice foreign law CPLRproof of sister state law New Yorkjudicial notice statute New York court