mudslinging
noun
Definitions
Casting aspersions with intent to discredit.
Example: The campaign degenerated into mutual mudslinging, each candidate trying to tarnish the other's reputation and looking bad in the process.
An act of making damaging or spiteful remarks with the intent to discredit.
Example: The mudslinging didn't help expand the media coverage of the issues; all that was reported was the mudslingings.