Maryland appellate court applies good faith exception to GPS use because of prior adoption of Knotts rationale

The Court of Special Appeals of Maryland recently held that the good faith exception to the exclusionary rule from Davis applies to pre-Jones GPS use because of the state's adoption of the Supreme Court's decision in Knotts. Kelly v. State, Nos. 2479 & 2679 (Md. Ct. Spec. App. 2012). In case you're in need of a criminal procedure refresher, I'll go over what all of that means.

First, we know that the Fourth Amendment generally requires a probable cause search warrant in order to conduct a search. Thus, we have to know what is considered a "search." In 1983, the Supreme Court decided United States v. Knotts, in which police placed a beeper device in a container which was later given to the defendant and used to track his location. This act, according to the Court, was not a search.

The Knotts opinion has been applied to other technologies including global positioning systems (GPS). As law enforcement began using GPS devices on vehicles without search warrants, courts readily okayed the act, finding that it was not a Fourth Amendment act. Until the DC Circuit decided this issue in Maynard, each circuit deciding the issue had held that GPS use was not a search. The Supreme Court took the issue in United States v. Jones and held in January 2012 that it was, in fact, a search.

One of the issues that has developed from the Jones decision is whether GPS use prior to the Jones decision violates the Fourth Amendment. This is where things get a little more complicated.

Violations of the basic constitutional rule that searches require search warrants often results in any evidence acquired as a result of the violation to be excluded from trial under the exclusionary rule. However, there are several rules that allow for the evidence to be used regardless - one of them known as the good faith exception. There are several ways that the exception applies - one of them decided by the Supreme Court in Davis v. United States, which held that when there is "binding appellate precedent" that made it legal for law enforcement to do what it did, the evidence will be admissible.

Therefore, applying Davis, law enforcement in the Ninth Circuit could use GPS devices to track suspects prior to Jones because they had binding appellate precedent. Some courts have applied the principle more loosely, holding that a general consensus across the country allows the good faith exception to apply. Conversely, many courts have held that the exception does not apply because no appellate court had addressed the GPS issue. (There are exceptions to each of these and other decisions, too.)

Now, back to the Maryland case. Maryland didn't have binding precedent on GPS use specifically. The Court of Special Appeals didn't take the general consensus approach, but instead took one substantially more broad. Because, the court reasoned, the state "had recognized and applied the rationale of Knotts, the good faith exception would apply. As the court understood it, Davis "does not require there to be a prior appellate case directly on point, i.e., factually the same as the police conduct in question."

Federal courts in the Eleventh Circuit have held similarly, applying a 1981 beeper case.