Many of the THP dispatches can be found online so not all hope is lost. Knox district 1 is streamed with a delay. I’m not certain about Memphis and Chattanooga. Fall Branch District 5 is not. They all have at least one talk group they can switch to go encrypted so if anything is too secret squirrel you probably won’t hear it.
LE Mutual Aid talk groups are also regional. They usually have very little activity. Same for FD and EMS MA talk groups.
They are used a lot in the Knoxville area for Law Enforcement, so if you live near the Knoxville District or are ever in the Knoxville area, it is worth it to program them. It is not uncommon for LE MUTAID 4, LE MUTAID 5, and LE MUTAID 6 to be active during the week. They see usage just about every day of the week here, sometimes on the weekend and late at night as well. DEA, ATF, USMS, TBI, THP CID, KCSO, BCSO, LCSO, ACSO, and RCSO are the most active users. Some others like TDOC Probation and Parole, HSI, TNG Counterdrug, FBI, and others use them from time to but not too often. "1TNDIST2" is also commonly used in the Knox area for law enforcement ops. I would imagine the mutual aid talk groups for the Chattanooga area are pretty active. I have heard them when I am down that way. I heard that USMS uses law mutual up in District 5 but have not confirmed yet.
I have not heard an EMS MUTAID talkgroup acitve, and I have only heard FIRE MUTAID occasionally.