State Sen. Rob Marionneaux is facing ethics charges related to his law firm's involvement in litigation against the state Department of Transportation and Development.

It marks the second charge filed against Marionneaux by the Louisiana Board of Ethics on the same issue of failure to timely disclose the business arrangement between his firm and a state agency.

The earlier case involves his representation of a firm in a legal dispute with LSU.

Marionneaux told The Advocate on Thursday that his law partner Lewis Unglesby represents Coastal Bridge Company in the litigation against DOTD.

Marionneaux said he alerted the Ethics Board to the legal arrangement in the case that is now the subject of the Ethics Board charges.