[3] After he graduated from high school in 1973, he enrolled in the University of Puerto Rico and participated in various competitions as member of the track and field team of his alma mater.

On June 19, 1984, O'Ferrall was promoted to first lieutenant and assigned to the 101st Troop Command in San Juan, Puerto Rico, where he served as communication electronic officer, until February 1985.

On February he was assigned to Camp Santiago Joint Training Center in Salinas, Puerto Rico, as Communication Electronic Officer, during which he was promoted to the rank of captain (1985).

[4] In 1986, O'Ferrall earned his master's degree in business administration and management from Turabo University in Gurabo, Puerto Rico, and served as range control officer at Camp Santiago until October 1988.

In April 1997, O'Ferrall was named combat commander at Headquarters of the 201st Regimental School at Fort Allen in Juana Díaz, Puerto Rico.

From July 2001 to July 2002, O'Ferrall continued his military academic education and became the first Puerto Rican to attend the United States Army War College/ Senior Service College at Harvard University; upon completion, he was reassigned to Headquarters, State Area Command as Logistics Staff Officer and in September 2002 as Director, Secretary General Staff.

O'Ferrall became the first Hispanic and general officer from the Puerto Rico Army National Guard supporting a joint forces mission of this caliber.

[7] He is responsible for the supervision of over 2150 members from the United States Army, Marines, Navy, Air Force and Coast Guard as well as over 5000 civilian contractors and workers on the base.

Among O'Ferrall's responsibilities is to ensure that those under his supervision provide safe, humane, legal and transparent care custody of detained enemy combatants, conduct intelligence collection, analysis and dissemination for protection of detainees and personnel working in Joint Task Force-Guantanamo in support of the Global War on Terrorism, support the Office of Military Commissions to law enforcement and war crime investigations in planning for and on order to respond to Caribbean mass migrations operations.