Philippines' law criminalizes adultery and concubinage. Both are deemed “crimes against chastity” under the Revised Penal Code of the Philippines and are treated as sexual infidelity in the Family Code.

The law discriminates against wives. The crime of adultery can be committed only by a wife and her paramour. The husband need only prove that his wife had sexual intercourse with a man other than him.

The crime of concubinage can be committed only by a husband and his concubine, but it requires that the wife must prove that her husband has kept a mistress in the conjugal dwelling, or has had sexual intercourse under “scandalous circumstances” or lived together with his mistress in any other place.

The penalties are also quite different. For adultery the guilty wife and her paramour may be imprisoned for up to 6 years

For concubinage, the husband may be imprisoned for up to 4 years and 1 day, while his concubine may be merely “banished” but may not be imprisoned.

The laws work to the great disadvantage of women. There is no divorce in the Philippines and abandoned wives are often accused of adultery in order to force them to agree to their husband's petitions to nullify the marriage. The Philippine Commission on Women reports that, “In many cases, women who are faced by these threats are forced to forego legitimate custodial claims of their children while some are forced to give up their claims over conjugal properties, assets and the like.”