As a young man he worked as a cowboy, saving his money which he used to pay to attend the Valparaiso Normal School when he was 30.

[5] In 1904, Riggs became a member of the Cochise County board of supervisors, elected for a four-year term.

[10] In April 1914, he announced his intention to run for one of the two state senate seats from Cochise County.

The primary was held on September 8, and by the 13th, 32 out of 46 precincts had reported in, with Roberts solidly in second place with 1348 votes, behind Riggs with 1655, but in front of Sims with 1209.

[12] However, two days later, a week after the election, there was only a single district remaining, and Roberts lead had disappeared and Sims now led him by 16 votes.

[4][20] He was married twice, his second wife's name was Cora, and they had a son, William Jr., who served in the infantry in the Pacific Theater during World War II.