Tennessee Code Title 49. Education § 49-6-4107

(a) A teacher, principal, school employee or school bus driver, in exercising the person's lawful authority, may use reasonable force when necessary under the circumstances to correct or restrain a student or prevent bodily harm or death to another person.

(b) Subsection (a) does not authorize use of corporal punishment by a person not permitted to administer corporal punishment under § 49-6-4103 or chapter 6, part 44 of this title.

(c) Subsection (a) does not authorize restraint or isolation of students for whom restraint or isolation is prohibited under chapter 10, part 13 of this title.

(d) A teacher, principal, school employee, or school bus driver using reasonable force in exercising the person's lawful authority in accordance with this section is immune from civil liability arising from the person's action pursuant to § 39-11-622, unless the teacher's, principal's, school employee's, or school bus driver's conduct is grossly negligent, reckless, or intentional misconduct. A person who is immune under this section is not the proximate cause of any resulting injuries.