In the Notice of Hearing, the ALJ will say that you have a right to call witnesses to testify on your behalf. In reality, ALJ’s generally hate witnesses and will try to discourage claimants from calling them (and sometimes outright prevent them from calling them).
Whether you should call witnesses depends on the case. In the vast majority of cases, witnesses are not helpful. Cases are generally won or lost based on the strength of the medical evidence, not the witness testimony. Moreover, most witnesses simply corroborate a claimant’s testimony without providing much new information. Additionally, there is limited time for the hearing, so if time is used for witnesses that can result in less time for the claimant to speak. Finally, and most importantly, using a witness has the potential for causing great harm. Witnesses are typically kept outside the hearing room until it is their turn to testify. They have no idea what the claimant may have already said. Thus, there is a big potential risk that the witness might contradict the claimant’s testimony. In our experience, whenever a claimant brings a witness, and that witness contradicts the claimant’s testimony, the ALJ will frequently use the contradiction as a basis to undermine the claimant’s credibility and possibly deny the case.
You should consider calling a witness if you have difficulty remembering facts, understanding questions, or articulating your problems. In some cases, such as epilepsy cases, a witness can be critical; people who suffer from grand mal seizures are unconscious and cannot describe their seizures.
If you do call witnesses, remember the adage “less is more.” Try to keep the witness testimony brief and to the point, and try to avoid calling multiple witnesses. There is no need to belabor any point.