My understanding is that (some) law enforcement agencies have been more than happy to drop cases rather than subject investigative tools to proper scrutiny[0]. They have no qualms resorting to "parallel construction"[1], and simply using the inadmissible (sometimes illegal) evidence to find admissible evidence.

[0] https://arstechnica.com/tech-policy/2015/04/fbi-would-rather...

[1] https://en.wikipedia.org/wiki/Parallel_construction