Mark W. Hennessy was a Georgia Republican and one of the "fake electors" who took part in Kenneth Chesebro's plot to submit fraudulent certificates of ascertainment favoring 2020 presidential candidate Donald Trump rather than the true winner of Georgia's electoral votes, Democrat Joe Biden. The plot failed, as Vice President Mike Pence refused to certify the fraudulent slates, and the Georgia "fake electors" were investigated by Fulton County district attorney Fani Willis for forgery and conspiracy.