Born in East Hatley, Compton County, Quebec, Canada,[1] Boynton received a Bachelor of Business Studies degree from Glasgow Normal School (now Western Kentucky University) in 1888 and a Bachelor of Laws from the University of Michigan Law School in 1891.

He was the United States Attorney for the Western District of Texas from 1907 to 1912, and then returned to private practice in Waco until 1924.

[2] On December 16, 1924, Boynton was nominated by President Calvin Coolidge to a seat on the United States District Court for the Western District of Texas vacated by Judge William Robert Smith.

Boynton was confirmed by the United States Senate on December 17, 1924, and received his commission the same day.

He assumed senior status on May 1, 1947, serving in that capacity until his death.