(Portland, OR) -- Authorities in Portland, Oregon won't move forward with a criminal prosecution of former Vice President Al Gore in a sex assault case. The "Washington Post" reports the reason for dropping the case is insufficient evidence. A massage therapist had accused Gore of sexually assaulting her in 2006. The case was reopened in June after the woman told the "National Enquirer" that Gore attempted to force her to have sex with him. Gore acknowledged he got a massage from the woman while staying at a Portland hotel but denied assaulting her.