Argument: Consensual adult incest should not be confused with abusive incest
Ashley Turner. "Incest, Inbreeding, and Intrafamilial Conflict: Analyzing the Boundaries of Sexual Permissiveness in Modern North America". Springer New York. December 8, 2007 - if we are to analyze this effect in any meaningful manner, we must first take care to differentiate the various forms of incest from one another, and to study their consequences separately so that any effects due to relationship status, rather than to incest per se, can be taken into account. We must also ensure that we separate our definition of incest from that of non-consensual sex—that is, incest that occurs in couples in which one partner is too young to legally consent should be distinguished from incest that occurs between two consenting adults (i.e. incest per se), and the effects of these two variants of incest should as well be assessed separately. Using these careful definitions, it can be logically argued that incest on its own should not be prohibited in modern North American society, as the damage to our freedom that such a prohibition would entail cannot be justified by what little unambiguous evidence there is to support its case.
"Sexual Ethics: Consensual Incest". A Nadder. October 13th, 2008 - There's the obvious correlation with child abuse but just like fantasies of pedophilia and acts of child abuse have merged in our minds so have incest and child abuse. If you're raping someone, the presence of incest does nothing to change the brutal nature of the act. If we keep incest statutes as a legal instrument against abusers, we should at least admit it.