President Trump refers to Barack Obama as the most corrupt president in the history of the United States.
Comparison Trump is drawing isn't really about scale, it's about the double standard. Nixon's presidency is treated as the textbook case of executive corruption because the system held him accountable.
IRS under Lois Lerner systematically delayed and scrutinised tax exempt applications from conservative groups in the run-up to the 2012 election a fact confirmed by the agency's own inspector general.