The Salt Lake County District Attorney's Office and the Davis County Attorney's Office are also investigating whether Utah Attorney General John Swallow broke any state laws.
Salt Lake County District Attorney Sim Gill said given the string of allegations surrounding Swallow, the latest probe raises more questions.
Gill confirmed he, and Davis County District Attorney Troy Rawlings have been working closely with federal investigators for months to determine if any laws were broken. Gill does not specifically name John Swallow or Mark Shurtleff in this probe.
Swallow is currently under investigation by the U.S. Justice Department, where he's accused of bribery in a federal fraud case involving a St. George businessman. The State is also investigating Swallow for possible campaign finance violation laws, and the State Bar is looking into possible ethics violations.
In a statement, Sim Gill says the purpose of cooperating with other agencies has been to share resources and information, and where and when appropriate, to determine what the proper venue may be fore filing any potential state criminal charges, if any.
Paul Murphy, Director of Communications for the AG's office, said this is the first he's heard of any investigation by Salt Lake and Davis County officials.