INCEST IS BLEST?

*

http://nypost.com/2014/10/29/new-york-state-blesses-incest-marriage-between-uncle-niece/

NY State blesses ‘incest’ marriage between uncle, niece

The state’s highest court has toppled a cultural taboo — legalizing a degree of incest, at least between an uncle and niece — in a unanimous ruling.

TG: I thought the "slippery slope" was a fallacy?