Madness does not allow marriage to be contracted, because consent is required.

Explanation

Consent is the essence of marriage, and insanity destroys the capacity to consent — cite this to annul a marriage entered into by a person who, at the time of the ceremony, was incapable of understanding the nature of the contract.

Where this applies

• A man suffering from severe schizophrenia participates in a wedding ceremony; his family seeks annulment on the ground that his mental illness rendered him incapable of giving the consent marriage requires.
• A bride is in a dissociative state during the ceremony due to a traumatic brain injury; the court voids the marriage because madness prevents the formation of the consent that is essential to the contract.
• A family discovers that their elderly father, deep in the fog of dementia, was married by an opportunistic caretaker; the court annuls the union because no valid consent was possible.