The 23-year-old, who was axed from the Canberra Raiders for his off-field antics in 2008, is reported to have set the man’s pants alight on Airlie Beach in North Queensland on New Year’s eve.
The victim suffered burns as a result of the incident, which has been described as a prank.
A club statement read: “While no complaint has been made to the Queensland police the club has a responsibility to complete a thorough investigation.”
Carney spent last season in exile with Atherton Roosters after being de-registered by the NRL following a string of alcohol-related incidents.
However Carney has reportedly told club officials that the victim was in fact a friend and no malice was intended.