FBI spokesman Christopher Allen told the Post-Dispatch last month that the existence of the technology is not considered sensitive — just the way it works.

He provided a statement Friday that said, in part, that the nondisclosure agreement “should not be construed to prevent a law enforcement officer from disclosing to the court or a prosecutor the fact that this technology was used in a particular case. Defendants have a legal right to challenge the use of electronic surveillance devices, and not disclosing their use could inappropriately and adversely affect a defendant’s right to challenge the use of the equipment.”

Last week, Allen told the Washington Post that the FBI has not invoked a provision of the agreements that would force officials to drop a criminal case.

But simply acknowledging the use of StingRays will not be enough for defense attorneys.