In the Philippines, where divorce remains legally unrecognized (except for Muslim Filipinos and certain cases involving foreign spouses), Annulment and Declaration of Nullity of Marriage are the primary legal avenues for dissolving or voiding a marital union. While often used interchangeably in casual conversation, they are distinct legal concepts under the Family Code of the Philippines.

I. Annulment vs. Declaration of Nullity

Before diving into the process, it is crucial to distinguish between a marriage that is "voidable" and one that is "void from the beginning" (void ab initio).

Annulment (Article 45): Applies to a marriage that is considered valid until it is set aside by a court order. The grounds for annulment usually exist at the time of the celebration of the marriage.
Declaration of Absolute Nullity (Articles 35, 36, 37, 38): Applies to marriages that were never valid from the start. These marriages are legally non-existent.

II. Grounds for Annulment and Nullity

The Family Code provides specific, narrow grounds for seeking these legal remedies.

1. Grounds for Annulment (Voidable Marriages)

Pursuant to Article 45, a marriage may be annulled for any of the following:

Lack of Parental Consent: If either party was between 18 and 21 years old and married without parental consent (unless they continued to live together freely after reaching 21).
Insanity: If either party was of unsound mind at the time of marriage.
Fraud: Obtaining consent through deceptive means (e.g., non-disclosure of a prior conviction involving moral turpitude, concealment of pregnancy by another man, or concealment of a sexually transmitted disease).
Force, Intimidation, or Undue Influence: If consent was obtained through coercion.
Physical Incapacity: If either party is physically incapable of consummating the marriage (impotence) and such incapacity appears to be incurable.
Serious Sexually Transmitted Disease (STD): If either party has an STD found to be serious and appears to be incurable.

2. Grounds for Declaration of Nullity (Void Marriages)

The most common grounds include:

Psychological Incapacity (Article 36): This is the most frequently cited ground. It refers to a party's inability to comply with the essential marital obligations due to a psychological condition that existed at the time of the marriage, even if it only manifested later.
Absence of Formal Requisites: Lack of a valid marriage license or a person unauthorized to solemnize marriages (subject to certain exceptions).
Bigamous or Polygamous Marriages: Marrying while a previous valid marriage is still subsisting.
Incestuous Marriages: Marriages between ascendants and descendants, or siblings.
Public Policy Violations: Marriages between first cousins or between a step-parent and step-child.

III. The Legal Process: Step-by-Step

The process is rigorous and can take anywhere from one to four years (or longer), depending on the court's docket and the complexity of the case.

Verification and Psychological Evaluation: If filing under Article 36, the petitioner usually undergoes an evaluation by a clinical psychologist or psychiatrist to establish "psychological incapacity."
Filing the Petition: Your lawyer files the Petition for Annulment/Nullity in the Regional Trial Court (RTC) of the province or city where either the petitioner or respondent has resided for at least six months.
Summons: The court issues a summons to the respondent. If the respondent cannot be located, "service by publication" in a newspaper may be required.
Investigation by the Public Prosecutor: The State (through the Office of the Solicitor General) intervenes to ensure there is no collusion between the parties to "fabricate" a ground for annulment.
Pre-Trial Conference: The court sets issues to be resolved and explores the possibility of a settlement regarding property and custody (not the annulment itself).
Trial: Both parties present evidence and witnesses (including the psychologist, if applicable).
Judgment: The court issues a decision. If granted, the court will issue a Decree of Annulment/Nullity.
Registration: The decree must be registered with the Local Civil Registrar and the Philippine Statistics Authority (PSA).

IV. Documentary Requirements

To initiate the process, you will generally need the following documents:

PSA Marriage Certificate (Original copy)
PSA Birth Certificates of the spouses and their children
Barangay Certificate of Residency (to prove venue jurisdiction)
Psychological Evaluation Report (if applicable)
Evidence of Grounds (e.g., medical certificates, affidavits of witnesses, or police reports in cases of fraud/coercion)
List of Properties (if there are common assets to be partitioned)

V. Essential Considerations

Cost: Legal fees, psychological evaluations, and filing fees can be significant. It is considered a costly procedure in the Philippines.
Custody and Support: The court will also rule on the custody of minor children and the amount of child support, prioritizing the "best interests of the child."
Property Relations: The court will oversee the liquidation and distribution of the Absolute Community or Conjugal Partnership properties.

Note: Because the Philippine legal system is adversarial, it is highly recommended to consult with a lawyer specializing in Family Law to ensure that the grounds cited are legally tenable and the evidence is sufficient.

Would you like me to draft a sample checklist of the specific documents you need to gather for your lawyer?