Supplemental discovery is a later set of questions or requests for information from the opposing party in a lawsuit, such as in the form of interrogatories or requests for production. Supplemental discovery, seeks to find out what has changed since the initial disclosure to uncover any new information that is crucial to the case. After answering a discovery request, the answering party has a duty to provide further information if the answer later turns out to be inaccurate.
It is governed by rules of civil procedure, which vary by state, as well as the court's deadline for discovery in the case. In most states, there are certain standard interrogatories to help you find out new information: update, supplemental, surveillance and expert interrogatories.
The following is an example of a local rule governing supplemental discovery:
R 205.1275 Supplemental discovery and prehearing procedure
The tribunal may issue orders making changes in the prehearing and discovery procedures fixed by R 205.1250 to R 205.1270 as justice may require to achieve a full and fair hearing of a matter before the entire tribunal.