What is ERISA?
“ERISA is a federal law that sets minimum standards for retirement plans in private industry.”
“The Employee Retirement Income Security Act of 1974, or ERISA, protects the assets of millions of Americans so that funds placed in retirement plans during their working lives will be there when they retire.”
Protection against creditors
One advantage that the ERISA law offers is that creditors cannot get at the money you have in an ERISA-covered plan.
However, access can be granted as part of a divorce settlement. Additionally, the IRS and other arms of the federal government can get access to your ERISA-covered plan for payment of federal tax debt or federal fines and penalties.
This is just a very short take from a very wide-ranging and complicated law you can read at: https://www.dol.gov/general/topic/retirement/erisa