If it appears to the governor that the power of any county is not sufficient to enable the sheriff to execute process delivered to that sheriff, the governor may, on the application of the sheriff, order a posse or military force as is necessary from any other county or counties.
Power of governor to order posse or military force from other county
Tenn. Code Ann. § 38-3-112, under Public Officers Preventing Commission of Offenses.
Tenn. Code Ann. § 38-3-112