He served as the Attorney General of the Philippines from 1927 to 1932, as part of the American colonial Insular Government.

[2] He was named Judge Advocate General and after the Japanese conquest of the Philippines was forced on the Bataan Death March.

After the conclusion of World War II, he was selected to serve as a Justice of the Philippines on the International Military Tribunal for the Far East.

In 1903, he was dispatched to the United States under the 'Pensionado' scholarship programme and studied at Santa Ana High School.

Jaranilla was portrayed by Bert Matias in the NHK miniseries Tokyo Trial (2016).