Q: Is it illegal in the state of Florida for 1st cousins to have sexual relationship? Asking before I involve the law.

A: See Florida statute 826.04...There are some critical facts missing that may alter the response.

A: That is a very interesting question.

Florida Statute 826.04 provides as follows: 

"Incest.—Whoever knowingly marries or has sexual intercourse with a person to whom he or she is related by lineal consanguinity, or a brother, sister, uncle, aunt, nephew, or niece, commits incest, which constitutes a felony of the third degree, punishable as provided in s. 775.082, s. 775.083, or s. 775.084. …"

The problem is that, there being no definition of "lineal consanguinity", and no limitation on the degree of lineal consanguinity for which intercourse is prohibited, it could, in theory, be extended to very distant relatives (such as 958th cousins 924 times removed).

A: I agree with the answers provided by the other two lawyers; however, I write to point out there is another perhaps more important issue hiding in the asker's question: Namely, that one of the cousins is a minor.

A: I don't read the question to suggest that the minor child, who " lives with them" is one of the two first cousins who apparently have a sexual relationship. But upon further reflection, I think the statute which prohibits sexual intercourse with members of three groups (persons to whom one is related by lineal consanguinity or siblings, or siblings' children) suggests that LINEAL consanguinity means only the relationship between a parent, child, grandchild, etc. Thus, intercourse between first cousins apparently is NOT a crime, albeit abhorred by societal norms.