Suppose that a magistrate is asked to issue a search warrant for a particular residence. Based on the information presented to her by the applicant, the magistrate believes that there is approximately a 25% chance that a search of the residence will result in the discovery of evidence of the crime under investigation. When deciding whether to issue the warrant, does it matter what the crime is? Should the magistrate interpret probable cause differently when the crime is the kidnapping of a young child than when the crime is the counterfeiting of Gucci purses? The same issue arises for an officer considering whether he has probable cause to arrest a suspect.
There are good arguments on both sides. Requiring a different degree of certainty for different crimes would complicate the magistrate’s or officer’s job, and there is little agreement on which crimes are most serious, meaning that the probable cause standard would vary from one officer or judicial official to another. On the other hand, the ultimate command of the Fourth Amendment is reasonableness, and it seems reasonable to allow the police more leeway in investigating serious crimes.
The Supreme Court has never answered this question. Some of its decisions arguably support a unitary interpretation of probable cause. See, e.g., Dunaway v. New York, 442 U.S. 200 (1979) (“The [probable cause] standard applie[s] to all arrests, without the need to ‘balance’ the interests and circumstances involved in particular situations.”). But others emphasize that the probable cause standard is a compromise between the need to protect individuals’ privacy and the need to protect society, see, e.g., Brinegar v. United States, 338 U.S. 160 (1948), and society needs more protection from serious offenses than from minor ones. (And individuals’ privacy needs more protection from greater intrusions than from lesser ones, a point that the Court has recognized in some contexts. See, e.g., Schmerber v. California, 384 U.S. 757 (1966) (adopting a higher-than-probable-cause standard for searches that require intrusion into the human body).)
There’s relatively little case law on point in the lower courts, with the exception of the Seventh Circuit, which has a line of authority endorsing a sliding-scale approach to probable cause. Pasiewicz v. Lake Co. Forest Preserve Dist., 270 F.3d 520 (7th Cir. 2001) (accepting the claim that “officers need a greater quantum of evidence when making arrests for less serious crimes”); Mason v. Godinez, 47 F.2d 852 (7th Cir. 1995) (finding an “inverse” relationship between the seriousness of a crime and the amount of proof needed to constitute probable cause); Llaguno v. Mingey, 763 F.2d 1560 (7th Cir. 1985) (probable cause is not a “point but a zone”). Professor LaFave’s treatise collects a few other cases. Wayne R. LaFave, Search and Seizure § 3.2(a) (4th ed. 2004). I’m not aware of any North Carolina cases on this issue.
Finally, the issue has perplexed the commentators, though it appears that a majority believe that the seriousness of the crime under investigation may be considered when assessing probable cause. See LaFave, supra (discussing both sides of the issue, and collecting cases and authorities, without reaching a firm conclusion); Eugene Volokh, Crime Severity and Constitutional Line-Drawing, 90 Va. L. Rev. 1957 (2004) (arguing in favor of distinguishing between crimes based on severity, but acknowledging the practical difficulties of this approach); Ronald Bacigal, Making the Right Gamble: The Odds on Probable Cause, 74 Miss. L.J. 279 (2004) (“When computing the odds for probable cause, it seems obvious that a low level of probability should suffice when the stakes involve a terrorist threat. Conversely, we would expect that a high level of probability must be satisfied when the stakes are limited to the possible escape of an illegal smoker.”).
Returning to the question with which we began, it seems to me that the legal authority weighs slightly in favor of allowing a law enforcement officer or a judicial official to consider the seriousness of the offense when deciding whether probable cause exists. The Supreme Court may choose never to recognize that point, for fear of sowing uncertainty and litigation by fragmenting the probable cause standard, but as an empirical matter, I would be very surprised if officers and judicial officials didn’t consider the severity of the crime, at least subconsciously, when making probable cause determinations.