Boldt was a lifelong member of the Sigma Chi fraternity and served as a Grand Trustee for 6 years, from 1957 to 1963.

[2] Boldt's most notable (as well as controversial) decision was his opinion in United States v. Washington (1974), which upheld tribal fishing rights under several treaties.

Boldt declared a mistrial and sentenced the defendants to up to a year in prison for contempt of court.

[1][6] Boldt suffered from Alzheimer's disease during his final years, and died on March 18, 1984, at the Veteran's home in Lakewood, Washington, survived by his wife, three children, eight grandchildren and a great-grandchild.

[7] A decade after his death, tribes excluded from his ruling unsuccessfully sought to access his medical records to determine whether he suffered from the disease while he oversaw the fishing rights case.