In a teshuva issued by the Conservative Movement entitled Rituals and Documents of Marriage and Divorce for Same-Sex Couples by Rabbis Elliot Dorff, Daniel Nevins and Avram Reisner, it is claimed in a few places that the prohibition on intimate homosexual relations are on a rabbinic level. A few quotes from the teshuva state:
We acknowledged in our responsum that same-sex intimate relationships are comprehensively banned by classical rabbinic law
We concluded that for observant gay and lesbian Jews who would otherwise be condemned to a life of celibacy or secrecy, their human dignity requires suspension of the rabbinic level prohibitions so that they may experience intimacy and create families recognized by the Jewish community.
How do these rabbis arrive at the conclusion that homosexual relations are forbidden only on a rabbinic level? How do they explain the verse in Vayikra 18:22?
וְאֶת זָכָר לֹא תִשְׁכַּב מִשְׁכְּבֵי אִשָּׁה תּוֹעֵבָה הִוא:
Thou shalt not lie with mankind, as with womankind; it is abomination. (JPS)