In order to obtain an annulment you must prove either that the marriage is void or voidable.
A void marriage is an incestuous or bigamous marriage. A marriage may be voided on the grounds of the age of the petitioner (less than 18) upon marriage, prior existing marriage, unsound mind, fraud, force, or physical incapacity.
Remember that you would need to fully prove your ground for annulment, and this may not be easy to do. An annulment in California is not a divorce. It is a legal proceeding in which a marriage is declared invalid. Legally speaking, if an annulment is granted, the marriage never happened. This means that there is no property to divide, and neither child support nor spousal support will be awarded. Unlike a divorce proceeding, an annulment always requires a trial, even if the other party agrees the marriage should be annulled. Also unlike a divorce, there is no waiting period in an annulment. The court can declare the marriage did not exist without having to wait six months as the parties must do in a California divorce.
If one party is already married at the time he or she attempts to remarry, the second marriage will almost never be valid (there are some exceptions to this rule). Therefore, the parties will qualify for an annulment. Another basis to dissolve a marriage through an annulment in California is fraud. Fraud is by far the most common basis for an annulment. An annulment based upon fraud requires (1) a misrepresentation, (2) the injured spouse only learned of the misrepresentation after the parties married, (3) had the injured party known the truth he/she never would have married, and (4) the annulment was filed shortly after the truth was discovered. For instance, an annulment would be granted if one spouse made the other believe that he or she wanted to get married out of love, but the injured spouse later discovered the true motive of the marriage was to qualify for residency status in America. Similarly, if one spouse tells the injured spouse before marriage that he or she wants children, and the injured spouse later discovers the other party is impotent or sterile, the court would find fraud. On the other hand, one spouse having a hidden addiction does not qualify for an annulment.