E! Online reported the "In This Skin" singer's father, Joe Simpson, fired Shuter this week over the publicist's alleged mishandling of last week's rumors that his famous daughter was romantically involved with the 28-year-old singer.
The two singers' rumored romance, which Shuter allegedly spun to increase recognition of Simpson's new album, was featured in People magazine on Aug. 31 and Mayor's supposed dismissal of Simpson later became cover page material for Us Weekly.
This week, the 26-year-old Simpson appeared on "The View" to state that she was not dating the Grammy award-winning singer and sources close to Mayer have dismissed such rumors as well.
In reference to Shuter, one source said the recent spate of rumors was "100 percent Shuter. He broke all the rules of the game. He's a pathological liar. I wonder how much Jessica even knew what he was up to," the report said.
TMZ.com reported that both Joe Simpson and Shuter had no comment on the matter.