Adjective
ad litem (not comparable)
For the purpose of a legal case, as in guardian ad litem.
A former cop turned guardian ad litem is the girl’s only advocate when Dad kidnaps them and tries to disappear. Source: Internet
“A person whose sole concern is, what is in the best interest of a child — a parent or a guardian ad litem — that role is desperately needed now.” Source: Internet
That was in my role as a guardian ad litem in South Carolina family court. Source: Internet