[4] In August 2007, Bantag was formally accused of attempting to murder a teenager in Caloocan when he was Navotas City Bureau of Jail Management and Penology (BJMP) chief.

[6] When Bantag was overseeing the Parañaque City Jail in August 2016, he was injured when a grenade exploded in the prison which also killed 10 detainees.

On October 23, 2016, 30 inmates staged a riot protesting against plans to segregate the 2,000 detainees of the prison charged for drug-related offenses and called for Bantag's removal as warden.

[8] Bantag was designated as Director General of the Bureau of Corrections (BuCor) by President Rodrigo Duterte on September 17, 2019.

His predecessor Nicanor Faeldon was dismissed for failing to head to Duterte's order to stop the release of 2,000 heinous crime convicts under the Good Conduct Time Allowance Law.

President Marcos ordered Justice secretary Jesus Crispin Remulla to place Bantag under preventive suspension for 90 days pending investigation on his role on the killing.