Opinion of the Court
common-law authorities had repeatedly condemned abortion and described it as an "unlawful" act without regard to whether it occurred before or after quickening. See supra, at ___.
Another amicus brief relied upon by the respondents (see Brief for Respondents 21) tries to dismiss the significance of the state criminal statutes that were in effect when the Fourteenth Amendment was adopted by suggesting that they were enacted for illegitimate reasons. According to this account, which is based almost entirely on statements made by one prominent proponent, important motives for the laws were the fear that Catholic immigrants were having more babies than Protestants and that the availability of abortion was leading white Protestant women to "shirk[] their maternal duties." Brief for Amici Curiae American Historical Association and Organization of American Historians 20.
Resort to this argument is a testament to the lack of any real historical support for the right that Roe and Casey recognized. This Court has long disfavored arguments based on alleged legislative motives. See, e.g., City of Erie v. Pap's A.M., 529 U. S. 277, 292 (2000) (plurality); Turner Broadcasting System, Inc. v. F.C.C., 512 U. S. 622, 652 (1994); United States v. O'Brien, 391 U. S. 367, 383 (1968); Arizona v. California, 283 U.S. 423, 455 (1931) (collecting cases). The Court has recognized that inquiries into legislative motives "are a hazardous matter." O'Brien, 391 U. S., at 383. Even when an argument about legislative motive is backed by statements made by legislators who voted for a law, we have been reluctant to attribute those motives to the legislative body as a whole. "What motivates one legislator to make a speech about a statute is not necessarily what motivates scores of others to enact it." Ibid.
Here, the argument about legislative motive is not even based on statements by legislators, but on statements made by a few supporters of the new 19th century abortion laws,
