Is it legal in Texas or Pennsylvania to marry your half cousin?

Answer 1

No, it isn't.

Pennsylvania

§ 1703. Marriage within degree of consanguinity.

All marriages within the prohibited degrees of consanguinity as set forth in this part are voidable, but, when any of these marriages have not been dissolved during the lifetime of the parties, the unlawfulness of the marriage shall not be inquired into after the death of either of the parties to the marriage.

(e) Marriage to relatives.--No marriage license may be issued to applicants within the prohibited degrees of consanguinity which are as follows:

A man may not marry his mother.

A man may not marry the sister of his father.

A man may not marry the sister of his mother.

A man may not marry his sister.

A man may not marry his daughter.

A man may not marry the daughter of his son or daughter.

A man may not marry his first cousin.

A woman may not marry her father.

A woman may not marry the brother of her father.

A woman may not marry the brother of her mother.

A woman may not marry her brother.

A woman may not marry her son.

A woman may not marry the son of her son or daughter.

A woman may not marry her first cousin.

§ 4302. Incest.

A person is guilty of incest, a felony of the second degree, if that person knowingly marries or cohabits or has sexual intercourse with an ancestor or descendant, a brother or sister of the whole or half blood or an uncle, aunt, nephew or niece of the whole blood. The relationships referred to in this section include blood relationships without regard to legitimacy, and relationship of parent and child by adoption.

Answer 2

Don't even think about it...