Immediately. Involving an attorney promptly in the long term disability claims process may help the insured person get the benefits she deserves early, or can make sure that all the necessary steps are taken to ensure the issues are properly presented to the insurance company if the case needs to be litigated. Also, because sometimes the insured person is too sick or disabled to understand how to get the insurance company all the information it needs, an attorney can help the insured provide the insurance company the information it needs to pay a valid claim.
However, and more importantly, under ERISA a claimant must first present all the evidence to the insurance company and appeal all of the policy's internal appeals before filing a suit. Once a suit is filed, a claimant may not submit more evidence to be considered, and no discovery is permitted regarding the merits of the claim; instead, a court reviews only those documents that were provided to the insurance company before it made its decision. While some discovery might be permitted into any conflict-of- interest by the insurance company, the degree of that discovery is usually litigated and often limited. This means that if you do not hire an attorney before you receive a final denial then your attorney cannot put any more evidence into the record save for extraordinary circumstances. Hire an attorney immediately after you get your first denial – do not appeal the case on your own under any circumstances!