citizen advocate
/ˌsɪtɪz(ə)n ˈadvəkət/(also citizen's advocate, citizens' advocate)
noun
1 US. A person employed to mediate between citizens and local government or other official agencies. Also: a person who represents the interests of (a section of) the community to a policy-making body, or who campaigns for a particular cause; a member of a pressure group, a lobbyist.
2Originally US. A volunteer who provides help to disabled, elderly, or vulnerable members of the community; especially one trained to represent to the relevant authorities the interests of a person with learning difficulties or other cognitive impairment, and to provide help with administrative responsibilities.
- Recorded earliest in attributive use..
Origin
1950s; earliest use found in Western Political Quarterly. In some forms from citizen + advocate.