The use of US court-sanctioned wiretaps is on the rise. According to the most recent figures available, the number of taps increased 17 percent last year over the previous year.
The latest federal Wiretap Report shows there were 4,148 non national security related wiretaps authorized in 2015. Not a single application was denied, the report notes. Of that total, 3,297 were granted an extension over the original time period authorized by the warrant.
Given all the access, just when should the cops hang up on the call they’re bugging? A federal appeals court recently provided the answer—introducing the “plain hearing” principle.
This guidance concerns when the cops know, or reasonably know, that the speakers on a call are outside the scope of the original warrant. The plain hearing principle is similar to the well-known “plain view” doctrine, which allows authorities to seize physical evidence unrelated to a warrant if it’s in plain view of the police during a search.
According to the 9th US Circuit Court of Appeals, this announced plain hearing doctrine means: (PDF)
The Fourth Amendment provides an exception to the warrant or probable cause requirement when police see contraband in “plain view.” We adopt a similar principle today and hold that the police may use evidence obtained in “plain hearing” when they overhear speakers unrelated to the target conspiracy while listening to a valid wiretap, without having complied with the Wiretap Act requirements of probable cause and necessity as to those specific speakers. However, the agents must discontinue monitoring the wiretap once they know or reasonably should know that the phone calls only involved speakers outside the target conspiracy.
With that theory in hand, the San Francisco-based appeals …