On Tuesday, the Supreme Court ruled that the use of trained police dogs to sniff around the outside of a suspect’s house without a warrant constitutes an unreasonable search, prohibited by the Fourth Amendment.

Although overshadowed by this week’s landmark oral arguments on the constitutionality of the Defense of Marriage Act and California’s Proposition 8 (which will be covered extensively in the May issue of Supreme Court Debates), the decision in Florida v. Jardines is a noteworthy one.

For instance, the case created some strange ideological bedfellows Conservative Justice Antonin Scalia wrote the majority opinion, joined by Justice Clarence Thomas and more liberal Justices Ruth Bader Ginsburg, Sonia Sotomayor, and Elena Kagan. Justice Samuel Alito wrote a dissent, joined by Chief Justice John Roberts and Justices Anthony Kennedy and the generally more liberal Stephen Breyer (although Breyer has displayed a penchant for backing the government in law-and-order-type cases.

The decision shows that there can be a majority of the Court’s justices who join across ideological divisions to place greater emphasis on personal liberties and property rights over the law-enforcement powers of the government.

Also of note is that just last month, in Florida v. Harris (the spotlight case of the January 2013 issue of Supreme Court Debates), the Court ruled that an “alert” to the presence of contraband by a trained police dog is enough to give police the right to search a car. Once again, the Court appears to place a greater emphasis on an individual’s right to privacy in their own home, rather than on public roads in an automobile. For instance, the Court has ruled that the Government needs a warrant to use infrared cameras to observe a house, to go into a person’s driveway to place a tracking device on a car, or for a police officer to peer through a window to look for criminal activity.

There are exceptions, however. In Brigham City v. Stewart (2006), the Court ruled that police can enter a home if they think an occupant is or is about to be seriously injured. In Kentucky v. King, the Court held that if police smell marijuana and hear what they think is the sound of evidence being destroyed, they can enter a home after knocking and announcing their presence. (Justice Alito, in his dissent, cited King, arguing that a police dog that detects the scent of contraband is not legally different from a human officer who smells marijuana coming from a house.)

Despite this decision, drug-sniffing dogs will continue to be a valuable tool for law enforcement. But, for the first time, the Court has placed limits on their use.