Which type of lobbyist is employed by the interest groups themselves?

An in-house lobbyist is employed directly by an interest group or organization, which positions them to represent the interests of that group effectively. Being part of the organization means they have insider knowledge of the group's goals, concerns, and strategies, enabling them to advocate more persuasively for the interests they represent.

In contrast, a contract lobbyist is typically an external consultant hired for their expertise or connections, a public advocacy firm lobbyist represents a broader range of causes, and an independent lobbyist generally works on their own, often for various clients. As such, an in-house lobbyist has a unique advantage in understanding the specific dynamics and objectives of the interest group they serve.