ERISA claims are regulated by a federal law known as the Employee Retirement Income Security Act (ERISA). This law applies to all employee benefits received through most employers. It does not apply to government employers, church employers, or some employers who offer self-funded benefit plans. Under ERISA, insurance benefits disputes are very streamlined. The employer, or Plan Sponsor, and insurer have specific legal requirements under ERISA related to the documents they have to provide you and their timeframes in which to do it.
If your insurer denies your claim for benefits, you must appeal the denial before you bring suit. You have six months to appeal. If the appeal is denied, you can then bring a lawsuit. Where ERISA is a federal law, all lawsuits related to it must be in federal court. ERISA permits minimal discovery in the lawsuit. There are usually no witnesses or depositions. There is also no jury trial. The judge will decide your lawsuit based on written arguments and possibly an oral argument. Under ERISA, there is no ability to seek punitive damages. The most a judge can award is the back benefits owed to you and reinstatement of your benefits. The insurer can still terminate them again at any time if it believes you no longer meet the criteria for disability.
Non-ERISA claims are claims for benefits brought by government employees, church employees, employees of employers with self-funded plans, and people who obtained their insurance policies outside of their employment. There is no required appeal before bringing suit in non-ERISA litigation, it is governed by the laws of your state for insurance, contract, and tort law. There will be discovery and depositions. There will be a jury trial with witnesses. And depending on the laws of your state, you can seek punitive damages if you can show that your insurer acted unreasonably.