What does father work as in the book matched?

In the book "Matched" by Ally Carter, Cassia's father, Thomas, works as a Citizen for the Society. He is a Custodian, tasked with maintaining the order and cleanliness of the community, including its gardens.

This is a key aspect of the society's structure, as the Citizens are expected to uphold the ideals of the government and contribute to the overall harmony of the community. However, as the story unfolds, we learn that Thomas has a secret past and holds dissenting views about the Society's control over their lives.