A federal judge says Richard Hobbs, a 48 year old convicted pedophile, has the right to perform as a clown for adults and children at Playland in Rye.  Manhattan federal Judge John Martin ruled that Hobbs was denied his First Amendment right to free speech when the county-owned facility told him he couldn't perform his balloon-bending act in the park.  In 2000 he had asked Playland for a permit but his request was denied by a park official who cited a regulation that bars soliciting in all Westchester County parks.  That official claimed Playland was not a public forum.  In 2001 Hobbs' second request was denied for the same reason and on additional grounds that, as a sex offender, he would be a danger to children.  In 1978 Hobbs pleaded guilty to child sex abuse after police accused him of luring an 11 year old boy into his office and fondling him.  He was sentenced in 1982 to nine months in jail in Pennsylvania for molesting a 14 year old boy on the way to and in a church where Hobbs performed as Saturday the Clown.   Martin found that while Playland had a right to bar people from soliciting in its amusement-park area, it's unconstitutional to bar them from other parts of Playland that are open to the public.