Final answer:
The ABA and AMA joined forces to secure legislation likely aimed at obtaining an Antitrust Exemption, allowing them to set professional standards without violating competition laws.
Step-by-step explanation:
Based on the provided context, the American Bar Association (ABA) and the American Medical Association (AMA) likely formed a united front to secure legislation for the purpose of Antitrust Exemption. This would align with historical efforts to reduce the power of monopolies and secure favorable legislation for professions or industries. Such exemptions would allow professional associations to set standards and rules without being subject to antitrust laws intended to prevent monopolies and promote competition. The ABA and AMA are well-established organizations that have historically been involved in both legal and medical reforms as well as professional standards-setting in their respective fields.