If you were laid off at the same time as other people, but believe you were chosen because of your protected class status, it is possible that this was discrimination. If your employer decided to include you in the layoff because of a protected class like race, color, sex, or national origin, you experienced unlawful discrimination.
Some employers offer severance packages to employees who are part of a layoff. Those employees may have to sign a severance agreement that includes a release of claims. By accepting the severance package, you would be giving up any right to make a discrimination claim. You should carefully read any document your employer asks you to sign during a layoff. Better yet, you should let a lawyer review it before you sign.