The woman, Joan Parker, was one of 2,000 gay rights supporters that showed up to the rally, with the "victim", James Edward Belcher, being one of 200 protesters that came in order to speak out against the gay lifestyle.
From the AP:
"'He was just waving his arms and has a Bible in one hand, up and down, and screaming at the top of his lungs, "sodomites" and "you're going to hell,"' Parker said in a phone interview. 'I thought he needed a hug. S'o I gave him a hug.'"
Belcher claims she tried to kiss him on the lips (which she vehemently denies), and has now charged her with assault. He claims her embrace "was just one of many attempts to silence the preaching to those in need of salvation who practice a death style that they call a lifestyle."
The police chief was as surprised as anyone else involved that the preacher has decided to press charges, but acceded that the act of unwanted touching could indeed constitute assault. Parker's "offense" could earn her up to 30 days of community service.