So why not ban first cousins alongside homosexuals? Either people who can't procreate should be allowed to marry (like the old Jerry Lee Lewises), or they shouldn't be allowed (like the homosexuals).

But even better: Indiana recognizes first cousin marriages from other states that do not have the age restriction, like Tennessee! Hmm...

Either way they need to be treated the same. Given that Indiana lets the Jerry Lee Lewis marriage proceed, it should allow the homosexual one to proceed as well. If not, then the distinction isn't based solely on procreation, it's also based on homosexuality. Q.E.D.

I believe he's demonstrably better at reading law than you are...