When your case comes before the judge, he has the option of approving your claim as filed, denying your claim, or issuing a partially favorable decision approving benefits but using a different onset date. Usually, when the judge changes your onset date he will use a more recent date, which will have the effect of reducing your past due benefit amount.
Why would the judge change your onset date? Most often the judge will do this because he has concluded that the medical evidence in your file does not support your original alleged onset date. You can expect this to happen if you alleged an onset date prior to the date you stopped working, or if your onset date was more than two or three years ago.
Some judges will choose a different onset date based on the presence of a medical test, such as an MRI or CT scan. This can be frustrating if, for example, you hurt your back three years ago, but could not afford an MRI until two years ago. Some judges just do not feel comfortable assuming anything, despite the very strong likelihood that your disc issues existed as of the time of your traumatic back injury and did not suddenly come into existence a year after your accident.
Some judges will change your onset date to your 50th or 55th birthday so they can use the grid rules to issue an approval. In these cases the judge may feel that you retain the functional capacity to perform some work so the only basis for approval would be the grid rules.
Often, during the actual hearing the judge will ask you and your attorney to consider voluntarily amending your onset date so that the judge can issue a fully favorable decision. In these cases you and your attorney will be given time to step outside and confer in private. If you do choose to voluntarily amend your onset date, make sure that you do not agree to a changed onset date that is after your date last insured for Title II SSDI without understanding the implications of doing so. If you agree to an onset date after your Title II SSDI insurance has lapsed, you would only be eligible for SSI, and SSI is subject to numerous offsets that can reduce or eliminate your SSI benefit.
If the judge does not ask you to voluntarily amend the onset date, or if you refuse to do so, the judge can issue what is known as a partially favorable decision. In such a case, you have the right to appeal the partially favorable decision but if you do so, you will also be appealing the favorable part and could end up with nothing. No benefits will be paid until your appeal is processed. Appealing a partially favorable decision, therefore, is a risky proposition.
State Agency adjudicators frequently issue partially favorable approvals with amended onset dates. You and your attorney will have to decide whether to accept the amended date and forgo thousands of dollars in past due benefits, or to continue with your appeal and appear before the judge.
Disability remains an all or nothing proposition in that there is no such thing as a partial disability award like there is with VA disability claims. Social Security judges, at this point, cannot find you 60% disabled and issue a decision accordingly. The only option they have is to change the onset date as described above.