225Texas, there is no specific channel or talkgroup used by the Harris County jail. If it is progarammed into their radio, and they are authorized to use it on a regular basis, jail units will occasionally appear. But for normal use, the following is what I have observed over the years:
Inside the jail, the telephone, intercom, and instant messaging are the primary forms of communication.
Outside the jail, the Criminal Justice talkgroup is used for coordinating with their base, and the District talkgroup is used where the transportation van is operating.
Nextel is used everywhere Nextel works, including the noisy direct connect. Personal cell phones are used everywhere they can get a signal. Both are not very effective inside, probably from all the concrete and steel.
Harris County is not like some of the area counties where one can monitor jail communications. I worry about the security at the jails if one can follow inmate movement from home. But, from what I've been told, the sheriff's of those counties want to remain informed of his deputys' actions. Personally, I would be worried about jail, transportation, and courthouse security, and providing intelligence opportunites over the airways is a big no-no. Besides, if there are problems, that's why supervisors are paid the "big bucks" to take care of the small stuff and inform the boss of the big stuff.