Short Answer 
The Patient Protection and Affordable Care Act (ACA), signed in 2010, enhanced parity laws initially established by the Mental Health Parity and Addiction Equity Act (MHPAEA) of 2008. It expanded coverage for mental health services, mandated equal benefits for mental and physical health, and promoted equitable treatment, leading to a more balanced healthcare system.
Step 1: Understanding the Legislation
The key regulation that enhanced parity laws in the U.S. is the Patient Protection and Affordable Care Act (PPACA), often referred to as the Affordable Care Act (ACA). Signed into law in 2010, it built upon the Mental Health Parity and Addiction Equity Act (MHPAEA) of 2008. This legislation aims to eliminate disparities in health coverage, addressing how insurance treats both mental and physical health services.
Step 2: Key Enhancements Under the ACA
The ACA introduced several crucial measures to strengthen parity laws, including:
- Expansion of Coverage: It broadened the requirements for insurance to include mental health services as part of essential health benefits.
- Equal Benefits Mandate: The Act mandated that benefits for mental health and substance use disorders must be comparable to those for physical health, ensuring access to necessary care.
- Aligned Coverage Options: It encourages insurance providers to enhance coverage options for all types of healthcare, promoting equitable treatment across the board.
Step 3: The Impact of the ACA
As a result of these enhancements, the ACA significantly reinforced the principles established by the MHPAEA. This has led to a more equitable healthcare system where mental health and substance use treatment are recognized and treated with equal importance as other health conditions. Thus, the ACA stands out as the regulation that best enhances parity laws, ensuring comprehensive care for individuals seeking treatment.