One of King's most significant prosecutions during this time involved the bribing of a juror in the 1968 trial of former West Virginia Governor William Wallace Barron and some of his associates, who faced corruption charges.

The jury foreperson confessed to accepting a bribe for acquittals, and Governor Barron subsequently pled guilty, received a twelve-year prison sentence, and became a government witness in the trials of two other people implicated in the bribery.

As an Assistant U.S. Attorney, King also prosecuted five Logan County officials on civil rights charges relating to electoral fraud.

He investigated alleged ethical violations by lawyers and represented the committee in proceedings before the Supreme Court of Appeals of West Virginia.

His investigation into the liquor industry and Alcohol Beverage Control Commission of West Virginia resulted in the conviction of more than forty individuals and corporations on charges including commercial bribery, mail fraud, extortion, and RICO violations.

"[2][3] President Bill Clinton nominated King to the United States Court of Appeals for the Fourth Circuit on June 24, 1998, after Judge Kenneth Keller Hall assumed senior status.

Senator Carte Goodwin to be nominated to replace him while the White House preferred J. Jeaneen Legato, a personal-injury lawyer in Charleston, West Virginia.