In July 1970, Nixon gives the go-ahead to the Huston Plan, which would greatly expand the scope of surveillance of anti-war protesters and other dissidents. A number of measures are concededly illegal.
A copy of the plan (one version of which called for detaining protesters in camps in the West) is leaked to the press, possibly by someone close to J. Edgar Hoover, who opposed some of the measures.
When Congress returns from its summer recess, a Senate committee led by Sam Ervin opens an investigation of alleged White House abuses of power.
The president's approval ratings, which had been in the 50s for much of the year, fall sharply.
In the 1970 election, Democrats pick up two seats in the Senate and 21 seats in the House. (One notable Republican casualty is Jack Kemp, who narrowly loses an open-seat race in Buffalo.)