Also think of the human and legal ramifications of jamming if a bad event were to happen, i.e. mass shooting, terrorist attack, etc., and an entity was jamming cell signals and people were unable to call for emergency services or help. When thinking of solutions ensure you think through emergency scenarios as well.
@CISOScott However, there are circumstances where it is legal to do i.e. Places of Correction, during examination periods, if authorised, by the authorities themselves to contain and control messages during a Terrorism situations, during a Civil Emergency situation, whereby the public go potty using attempting to jam up the mobile phone system, and then drain the 24 hour battery capability of the mobile tower itself. During a Civil Defense situation, the authority have the power to do a lot of things to protect the safety of lives. Hence many emergency systems use P25 radio systems, these expensive devices have multiple capability, VHF, UHF, Emergency Channels and Mobile phone capabilities, and in some cases even Satellite phone capabilities.
I think it comes down to the situation at the moment, and also who is the controlling entity.
I agree and respect both @denbesten and @CISOScott your respective perspectives, but there are circumstances whereby there is no other choice, but to jam the mobile phone cells, are specific network for a reason - whether it is for emergency or security reasons. Or potentially whereby a decoy mobile tower has been erected for dupe people or for investigation purposes.
Nothing in this world is black and white, it comes with shades of gray, and white, and there always overriding circumstances, whereby authorities have the power to veto or engage in certain circumstances. "lex est lex."