Yes, but only if the common areas are truly open to any member of the public. If the common areas are inside or accessibility is limited in any way to the public, the answer is probably no. Some case authority allows a K9 to sniff common areas of apartment buildings, including common hallways, which are open to the public (U.S. v. Makell (4th Cir. 2018) 721 Fed. Appx. 307, an unpublished opinion in Maryland; State v. Bowlds (2019) 2019 Minn. App. Unpub. Lexis 531; State v. Edstrom (2018) 916 N.W.2d 512, also Minnesota). However, other states’ case authority does not allow for a K9 sniff in common areas. In People v. Bonilla (2018) 2018 IL 122484, the Illinois Supreme Court held that a K9 sniff of the threshold of an apartment front door, even from a public hallway, is a violation of curtilage per the U. S. Supreme court opinion in Florida v. Jardines (2013) 569 U.S. 1, and therefore a Fourth Amendment violation. In Florida v. Jardines, supra, the Supreme Court held that in taking a drug detecting K9 onto the front porch of a home to determine if the K9 would alert was an invasion of the curtilage and therefore a violation of the Fourth Amendment. A fairly new case out of Iowa on the extent of curtilage is United States v. Burston (8th Cir.2015) 806 F.3d 1123. In that case, LE had information that drug activity may be going on in subject’s apartment, so handler took K9 to apartment building and had K9 sniff 6 to 10 inches away from window (which was about 6 feet from the front walk). The 8th Circuit Court held that to resolve curtilage questions, four relevant factors are considered: “the proximity of the area claimed to be curtilage to the home, whether the area is included within an enclosure surrounding the home, the nature of the uses to which the area is put, and the steps taken by the resident to protect the area from observation by people passing by.” Id. (quoting United States v. Dunn (1987) 480 U.S. 294, 301. Held, after analysis of these facts, this sniff was a violation of curtilage.
Based on what appears to be a trend to extend curtilage, LE should be very careful when sniffing what could be considered curtilage. Sniffs of apartment entry doors is going to be probably invalid. But a sniff of a common area open to the general public, such as a lobby, would probably be valid (how useful that might be is another question).