Seems to me a traditonal 'tail' would provide the needed probable cause to obtain a warrant; such PC might be observed within hours or a few days and provide more leads in terms of associates. Officers, deputies, agents, inspectors, etc. who have maintained good relationships with the prosecutors office and the courts should have no trouble obtaining permission to engage in such surveillance, many times without even the need to tail the subject.
Allowing any peace officer to place such a device without oversight suggests to me 4th Amendment Rights might easily be violated - oversight in terms of judicial review seems appropriate. I suspect the Justices will agree, especially those most conservative. Of course, given the recent Miranda revise, who knows? Given their activist nature and disdain for stare decisis I would not be surprised with anything done by by Roberts, Alito, Scalia and Thomas.
