Section 6648 - Exemption from arrest and service of process(a) If a person comes into this State in obedience to a summons directing him or her to attend and testify in such action in this State, he or she shall not, while in this State pursuant to such summons, be subject to arrest or the service of process, civil or criminal, in connection with matters that arose before his or her entrance under the summons.(b) If a person passes through this State while going to another state in obedience to a summons to attend and testify in such action in that state or while returning therefrom, he or she shall not while so passing through this State be subject to arrest or the service of process, civil or criminal, in connection with matters that arose before his or her entrance into this State under the summons.