Assume the following facts. Your client is arrested. No arrest warrant. No search warrant. But a firearm is seized lawfully. Search incident to arrest perhaps, but it doesn't matter. The point is: lawful seizure, but no warrant.
The police subsequently do a ballistics test on the firearm. (They also do an operability test, which I'll also talk about below.) The ballistics test produces a match with a shell casing found at the scene of a drive-by shooting a year before. The police then talk to your client. He confesses to the shooting.
Anything to suppress?
Yes. A careful analysis of the case law - but no case on point that I'm aware of - would suggest that the ballistics test without a search warrant is unlawful, because it reveals characteristics that are not plainly visible. This is more of a search than picking up shoes to see their tread or feeling a tire to feel it is warm, both of which constitute searches. State v. Cardell, 180 Or App 104,109-110 (2002); State v Portrey, 134 Or App 460,465 (1995).
The state will respond in a couple of different ways. Under State v. Munro, Or 545, 124 P3d 1221 (2005) and St v. Luman, 347 Or 487 (2009), they will argue that once the items have been lawfully seized, no warrant is required.
The two cases can be distinguished. First, under Munro, there was a warrant, and the opinion seems to be quite clear that - once the item has been seized via a warrant - any subsequent search of the item, even for reasons not originally envisioned in the warrant - are constitutionally kosher. But in the hypothetical I put forth above, there was no warrant that authorized the seizure of the firearm.
The Luman court stated as follows:
Once private parties have seized a piece of evidence, examined it, and delivered it to a police officer (thereby giving the police officer lawful possession of that evidence for criminal investigatory purposes), the police's officer's subsequent, confirmatory examination of that evidence involves no additional injury to any privacy interest of the property owner; any privacy interest that the property owner once may have had in that piece of evidence is destroyed, at least to the extent of the scope of the private search. State v. Luman, 347 Or 487, 495-496 (2009)
In Luman, the non-government agents had had already invaded the privacy and conveyed that information to the police. There was no more privacy to invade. (In this sense, privacy is like virginity, you can only lose it once.) But in the case I've described, the ballistics "privacy" has not yet been invaded.
Compare to State v. Binner, 131 Or App 677, 886 P2d 1056 (1994), where the defendant consented to a search of his blood to determine its alcohol content. That test indicated that his blood alcohol content was below the legal limit. Two weeks later, the police had his sample tested for THC content. The Court of Appeals held that the search of the defendant's blood for a chemical other than the chemical for which he consented to a search exceeded the scope of his consent, and therefore violated the defendant's privacy interest under Article I, section 9. Binner, 131 Or. App. at 683.
Binner is important for two reasons. First, it holds that testing is a search, since it reveals something about the evidence being tested that is not apparent to the naked eye.
Secondly, Binner holds that the lawful seizure of evidence - as the blood was lawfully seized - does not equal the right to search that evidence.
In Walter v. United States, 447 US 649, 65 L Ed 2d 410, 100 S Ct 2395 (1980), hundreds of boxes of 8 mm film were mistakenly delivered to a business. Employees there opened the packages. The exterior of the individual film containers had "suggestive drawings" and "explicit descriptions of the contents" indicating that "they contained obscene pictures." 447 US at 651-52. The employees contacted the FBI, and an agent picked up the packages. FBI agents subsequently viewed the videotapes using a projector, without first applying for a warrant. Id. at 652. The court noted that the FBI agents "lawfully acquired possession" of the films. Walter, 447 US at 649. Although the boxes evidently announced their contents, the court concluded that viewing the films without first obtaining a warrant violated the Fourth Amendment. Id. at 659.
The fact that FBI agents were lawfully in possession of the boxes of film did not give them authority to search their contents. Ever since 1878 when Mr. Justice Field's opinion for the Court in Ex parte Jackson, 96 US 727, [24 L Ed 877 (1877),] established that sealed packages in the mail cannot be opened without a warrant, it has been settled that an officer's authority to possess a package is distinct from his authority to examine its contents." Walter, 447 US at 653-54. [Emphasis added.]
Again, Walter holds that lawful possession does not give the state authority to test or inspect the seized item.
The state might try to make a "confirmatory testing" argument. This is the rule that testing a small amount of a controlled substance to confirm it is in fact that controlled substance does not require a search warrant. But any reasonable judge should be able to see the difference between a "testing X to confirm it is X" rule and "testing X to confirm that it will tell us something else."
This is why operability tests probably don't require a warrant. All the test does is determine if the firearm is a working firearm. Yes, there may be a sliver of a distinction that you may want to exploit, but I think it comes in as confirmatory testing. But a ballistics test is a whole different animal, because it reveals all sorts of characteristics beyond "this is a gun." And for the reasons above, I think a warrant - whether a warrant arising from the original seizure or a warrant to specifically conduct the ballistics test - is required.