The federal regulations: The new federal requlations implement part of the Mental Health Parity and Addiction Equity Act. They require affected health plans to provide roughly equivalent "non-quantitative treatment limits" for behavioral care and other forms of care. The federal regulations call for plans to show that provisions such as preauthorization requirements, barriers to access to facility care and the nature of the types of providers who can provide the care are similar for behavioral care and other forms of health care.

Related: MHPAEA: Feds post final mental health parity regulations

Supporters argue that non-quantitative treatment limitation regulations will help people fighting conditions such as depression, anxiety and alcoholism by keeping plans from imposing conditions that make using health coverage to pay for behavioral health care difficult or impossible.

Critics have argued that implementing the comparability analysis requirements a health plan will have to use to comply with the regulations will be difficult and expensive. Government impact analysts have predicted that the federal requirements will cost plans and insurers $656 million in the first year and $131 million per year in later years.

The proposed Colorado regulations: The Colorado version of the regulations would apply to health plans "subject to the individual and group laws of Colorado," including any group major medical plans subject to Affordable Care Act rules, short-term health insurance policies and student health insurance policies, but not to limited-benefit plans, such as hospital indemnity insurance policies.

Some provisions would affect medications used to treat behavioral health disorders. One would require health insurers or other types of coverage providers to put at least one medication approved for treating substance use disorder in the class of drugs that exposes the plan participants to the lowest level of out-of-pocket costs, and another provision would prohibit coverage providers from imposing prior authorization requirements on any prescription medication approved by the U.S. Food and Drug Administration for the treatment of substance use disorders.

ERIC's views: Clair emphasizes in the ERIC letter that ERIC member employers want to see federal regulators oversee multistate health plans, to minimize the state-to-state variations in benefits requirements.

"ERIC's concerns about the workability of the federal rule changes, as well as the enormous regulatory complexity, confusion and costs associated with the recent federal rule changes, cannot be understated," Clair writes.

If federal agency actions or court rulings change the federal standards, the changes "would create both an immediate conflict with the proposed Colorado regulations and a pressing need for state regulatory action to reconcile emerging differences," Clair says. "Employers would be left in limbo, unsure of how to comply and continue providing employee benefits while federal and state lawmakers attempt to resolve conflicting standards."