In Lambert v. California, 355 U.S. 225 (1957), the plaintiff was a convicted felon who as such, under the California Municipal Code, was required to register with the city if she remained (or intended to remain) in Los Angeles for more than five days. After living in Los Angeles for more than seven years, plaintiff was arrested on suspicion of another offense and then charged with violation of the registration law. On appeal to the United States Supreme Court on the grounds that the Code was unconstitutional, the Court opined: The question is whether a registration act of this character violates due process where it is applied to a person who has no actual knowledge of his duty to register, and where no showing is made of the probability of such knowledge. The Court addressed a city ordinance that criminally penalized felons who remained in Los Angeles more than five days without registering with the police. The Court held that a conviction under this registration provision violated due process when the defendant had no notice whatsoever that remaining in the city might lead to criminal prosecution. Id. at 228-30. The Court reasoned that the defendant's failure to register was "wholly passive" and her omission to act was, therefore, "unlike the commission of acts, or the failure to act under circumstances that should alert the doer to the consequences of his deed." Id. at 228. Under these circumstances, the Court concluded, the defendant could "not be convicted consistently with due process" without notice of the registration requirement. Id. at 229-30. The Supreme Court noted that criminal liability under the Ordinance could attach when the defendant's only activity was merely to be present in Los Angeles. The Lambert Court reasoned (at 229) that the concept of fair warning or notice that is an important part of due process of law required that "actual knowledge of the duty to register or proof of the probability of such knowledge and subsequent failure to comply are necessary before a conviction under the ordinance" could be had. "Were it otherwise, the evil would be as great as it is when the law is written in print too fine to read or in a language foreign to the community." (355 US, at 230.)