Strachan was H. R. Haldeman’s aide at the White House. As Haldeman explained to Nixon in an Oval Office meeting on March 20, 1973, Strachan’s job was to keep on top of everything that was going on concerning the Committee to Re-elect the President and the Watergate matter. After the break-in, Haldeman told Strachan to make certain their White House files were purged of embarrassing material. Later Strachan informed John Dean that DNC wiretaps, reports, and other information has been destroyed. Following the arrest of burglars and with Haldeman’s approval, Strachan sent $50,000 to Howard Hunt’s lawyer to buy the silence of those standing trial before Judge Sirica.

Strachan was indicted along with Haldeman, John Ehrlichman, Chuck Colson, and others by the United States District Court for the District of Columbia for conspiring to obstruct the Watergate investigation and making false statements to the grand jury. The grand jury named President Nixon as an “unindicted co-conspirator.” Here, too, Strachan played a role. Nixon received that designation in part because Strachan had stonewalled investigators with the president’s knowledge. Also, Nixon urged Ehrlichman to prepare Strachan to counter the testimony being provided by witnesses cooperating with the investigation. In the end, Strachan was granted immunity by the Senate Watergate committee in exchange for his testimony, making the prosecutor’s job difficult in bringing him to trial in Judge Sirica’s court, and the charges against him were dropped.