Section 8103. Costs where parties prevail upon separate issues

Upon the
  recovery of a judgment in favor of the plaintiff, the  court  may  award
  costs  in  the  action  to  a  defendant  without  denying  costs to the
  plaintiff, if it determines that  a  cause  of  action  upon  which  the
  defendant prevailed is not substantially the same as any cause of action
  upon which the plaintiff recovered the judgment.