§ 399 Witness privileged.

If you get called to court as a witness and have to travel to a county where you don't live, you can't be sued in that county just because you're there. This protection covers your whole trip: going to court, attending, and returning home.

The idea behind this rule is simple. People shouldn't be scared to show up as witnesses because they're worried about getting served with a lawsuit while they're there. Without this protection, someone could use a subpoena as a trick to lure a witness into their county just to sue them there.

So if you're only in that county because a subpoena told you to be there, you're safe from being sued locally during that visit. This lets witnesses focus on giving testimony without worrying about legal trouble somewhere else.