Members of the army or air national guard or the militia ordered into active service of the State by any proper authority shall not be liable, civilly or criminally, for any act or acts done by them in pursuance of duty in such service. The attorney general, the attorney general’s deputy, special deputy, or appointee shall defend all actions brought civilly or criminally for acts or omissions against any member of the army, air national guard, or militia which reasonably appear to have occurred during the performance of service under this chapter, or chapter 122, or during a call-up under § 121-30, and reasonably done within the line or performance of duty. No action or proceedings shall be prosecuted or maintained against a member of a military court or an officer or person acting under its authority or reviewing its proceedings, on account of the approval or imposition or collection of a fine or penalty, or the execution of any writ, warrant, execution, process, or mandate of a military court.