Illinois recognizes four grounds for annulment:
1) Illegality
– The marriage is illegal because it is prohibited by law:
– the couple are closely related by blood or adoption, or
– one spouse is still legally married to another person.
2) Lack of consent
– One spouse could not consent to the marriage due to being mentally disabled, under duress, or under the influence of drugs and/or alcohol at the time of the marriage.
3) Inability to consummate the marriage
– One spouse cannot engage in sexual intercourse, and the other spouse was not aware of this fact at the time of the marriage.
4) Underage marriage without parental consent
– One spouse was under the age of 18 and did not have parental consent to marry at the time of the marriage.
