He received a Bachelor of Arts degree from the University of Texas, Austin in 1972, and a Juris Doctor from Harvard Law School in 1975.

[2] On April 12, 1983, Hinojosa was nominated by President Ronald Reagan to a seat on the United States District Court for the Southern District of Texas vacated by Judge Woodrow Bradley Seals.

Hinojosa was confirmed by the United States Senate on May 4, 1983, and received his commission on May 5, 1983.

He was appointed as a commissioner on the United States Sentencing Commission by then President George W. Bush in 2003.

[1] Following the assumption of senior status by José A. Cabranes, Hinojosa is the longest-serving federal judge remaining in active service.