Born in Laoag City, Ilocos Norte, to former Digos City, Davao del Sur and Manila Court of First Instance Judge Elviro Lazo Peralta and public school teacher Catalina Madarang Peralta, Justice Diosdado M. Peralta started his career in government service in 1987 when he was appointed Third Assistant City Fiscal of Laoag City. In 1988, he was assigned to the Prosecutor’s Office in the City of Manila. He later became the Assistant Chief of the Investigation Division of the Office of the City Prosecutor in the early part of 1994.
In September 1994, Justice Peralta was appointed as Presiding Judge of Branch 95 of the Regional Trial Court (RTC) of Quezon City, which was designated as a Special Criminal Court on Heinous Crimes and, later, Drugs Cases. He was promoted to the Sandiganbayan in 2002, and became its Presiding Justice in 2008. In January 13, 2009, he was named as the 162nd Associate Justice of the Supreme Court. He is the third Presiding Justice of the anti-graft court to be appointed to the High Court.
As a prosecutor, he was recognized as the Outstanding Public Prosecutor of Manila for the year 1990-1991 by the City of Manila, and the Most Outstanding Public Prosecutor of the City of Manila in 1994 by the Department of Justice. He was also one of the five finalists for Outstanding Public Prosecutor given by the Foundation on Judicial Excellence in 1993. As a prosecutor, he concentrated on trial work rather than conducting inquest proceedings, and was the only one out of the many prosecutors who persevered and measured up to the exacting standards of then RTC Manila Judge, now Retired Supreme Court Associate Justice, Romeo J. Callejo Sr., whose Branch 49, a heinous crimes and drugs court, was revered to be the fastest in resolving cases.
As a trial court judge, he was awarded a Plaque of Commendation in 1999 by the Integrated Bar of the Philippines – Quezon City Chapter for his speedy and scholarly disposition of criminal cases. He was also awarded the 1999 Annual Pillars of the Criminal Justice System Award¸ given on the First Founding Anniversary of the Volunteers Against Crime and Corruption (VACC), and in 2001, he was again awarded by the VACC for his continuous and consistent speedy disposition of criminal cases. He is probably the only RTC Judge who has been recognized twice by the said organization for the said achievement.
He was conferred the Special Centennial Awards in the Field of Criminal Law, given by the Integrated Bar of the Philippines and the Supreme Court during the Court’s Centennial Celebration on June 6, 2001, for his “credible and no-nonsense management and expeditious disposal of heinous crimes and drug cases… [which] has visibly strengthened the Philippine Criminal Justice System and helped bolster and maintain respect, trust and confidence in our criminal courts.” He was likewise given the Judicial Excellence Awards 2002 (Chief Justice Ramon Avanceña Award for Outstanding Regional Trial Court Judge) by the Foundation for Judicial Excellence on June 14, 2002 which, providentially, was the same day as his appointment to the Sandiganbayan.
In the 1999 case of People vs. Fallorina, after merely three months and six witnesses, then Quezon City Judge Peralta imposed the death penalty on a policeman who used his service firearm to shoot an 11-year-old boy while flying his kite on a rooftop. A columnist from the national broadsheet opined that “[t]he speedy trial of Fallorina proves that the wheel of justice can move fast if the judges and other court personnel want to. A veteran prosecutor of Manila before he was appointed to the judiciary, Judge Peralta knows the ins and outs of prosecution and the tactics that defense lawyers usually engage in to delay criminal proceedings.”
In People vs. Manalili, he penned the first-ever conviction for plunder in 2001, when he sentenced a cashier of the Bureau of Internal Revenue (BIR) to two life terms for having diverted to and withdrawn from her bank account a total of ₱260,000,000.00 in withholding taxes paid to the BIR. An editorial of a national broadsheet noted that such conviction “sends a strong warning that corruption does not pay. It’s a warning long awaited in this country.” In People vs. Ovilla, he convicted a substantial number of police officers, including a Station Commander of Kamuning, Quezon City police station, who deliberately failed to file cases against suspected foreign drug-traffickers in exchange for money—the first and only conviction of Qualified Bribery under Article 211-A of the Revised Penal Code, as amended—and imposed the capital punishment for such crime for the first time since its introduction in 1993 under the Heinous Crime Law (R.A. No. 7659). He likewise convicted the most number of accused involved in big time drugs cases and other serious crimes, and meted the maximum penalty provided by law. He was also part of the Sandiganbayan Special Division which tried and convicted a former President of the crime of plunder.
As a staunch advocate of Continuous Trial in criminal cases, he consciously decided cases within the reglementary periods, and in accordance with law, jurisprudence, rules of procedure and the Constitution. At the time he was promoted to the Sandiganbayan, he left only about twenty-five (25) active cases, down from about six hundred cases (600) when he started as a trial judge. Even before the Supreme Court came out with a computerized case management information system, he is known to have his own version in the trial court, which resulted in efficient case-monitoring, expedited resolution of cases, and low caseload of his court docket.
During his term as Associate Justice, and later Presiding Justice, the Sandiganbayan registered the most number of cases decided on the merits because of the innovations he introduced, namely: stipulation on the testimony of witnesses, or adoption of affidavits and statement of witnesses as their direct testimony, subject to cross-examination, which were later adopted by other Associate Justices of the Sandiganbayan and incorporated in the Revised Guidelines for Continuous Trial of Criminal Cases. As a result, the long and tedious presentation of testimonies of witnesses has been greatly reduced. His efficiency in case management and advocacy for speedy disposition of cases was again put to test when he became an Associate Justice of the Supreme Court in 2009 and inherited the most number of cases at about One Thousand One Hundred Twenty-Eight (1,128) judicial and administrative cases. Due to sheer diligence and passion for work, he is consistent as one of the top-performers in adjudicating cases, which enabled him to reduce to about Three Hundred (300) cases to date, despite his various committee work and academic collaborations with the Philippine Judicial Academy (PHILJA).
Justice Peralta is an alumnus of the University of Santo Tomas Faculty of Civil Law where he studied as a working student and graduated in 1979. He obtained his undergraduate degree in Economics from the Colegio de San Juan de Letran in 1974, and started working at the age of twenty (20) as a Senior Clerk of Cosmos Bottling Corporation until 1986.
Prior to becoming a member of the Supreme Court, he was a professor, lecturer, resource person, and Bar reviewer in Criminal Law, Criminal Procedure, Remedial Law, and Trial Techniques at the UST Faculty of Civil Law, the Ateneo de Manila University, San Beda College of Law, the University of the East, and the University of the Philippines Law Center, among others. He has been a member of the Corps of Professors under the Department of Criminal Law of the PHILJA and remains to be an active lecturer thereof on its Orientation Program for Newly-appointed Judges, Pre-judicature Program and other training seminars.
He was given the Ulirang Ama Sectoral Award on Law and Judiciary from the Ulirang Ama Foundation in 2006 and was awarded as The Outstanding Thomasian Alumni by the University of Santo Tomas Alumni Association in 2008. In 2010, he was conferred the degree of Doctor of Laws Honoris Causa by the Northwestern University, Laoag City.
In 2014, Justice Peralta served as the Chairperson of both the 2014 Bar Examinations and the Special Shari’ah Bar Examinations, which prepared the present Rules in the conduct of the Special Shari’ah Bar Examinations that took effect in 2015.
He was a member of the Supreme Court Committees that prepared the Rules of Procedure for Environmental Cases in 2010 and the Rules of Procedure for Intellectual Property Rights Cases in 2011. He also acted as ex-officio Chairperson of the Judicial and Bar Council during the search for a new Chief Justice in 2012.
At present, Justice Peralta is the Vice and Working Chairperson of the Committee on the Revision of the Rules of Court (Mother Rule Committee), the Chairperson of the Sub-Committee on the Revision of the 1997 Rules of Civil Procedure, and the Chairperson of the Special Committee for the Rules on Inspection of the Philippine Competition Commission, the Special Committee for the Rules of Procedure for Admiralty Cases. He is also a member of the Board of Judges of the Society for Judicial Excellence and of the Sub-Committee on the Internal Rules of the Supreme Court, as well as the lead representative of the Judiciary Budget Committee that defends its budget before Congress since 2012. He is likewise a member of the following committees: Committee on the Rules on DNA Evidence; Committee on the Revision of the Philippine Benchbook for Trial Court Judges; the Judicial Reform Support Project Management Committee and Chairperson of its Component Working Committee for Component D; the Committee on Legislative-Executive Relations (LERCOM); and the Sub-Committee on Evidence.
He is the Chairperson of the Special Committee on Small Claims Cases, which drafted the revision of the Rules of Procedure on Small Claims Cases in 2015, and the Chairperson and main architect of the Special Committee on Speedy Trial which drafted the 2017 Revised Guidelines for Continuous Trial of Criminal Cases. Both rules of procedure show remarkable and significant improvement in reducing the duration of court proceedings, and in improving the trial courts’ compliance with the reglementary periods, which resulted in drastic case docket reduction and speedy disposition of cases.
He likewise serves as the Chairperson of the Special Committee on the Revision of the 2018 Internal Rules of the Sandiganbayan, as well as the Special Committee on the Rules of Procedure in Election Contests before the First Level Courts. He also spearheaded the adoption of the 2019 Guidelines on the Use of Videoconferencing Technology for Remote Court Appearance or Testimony of Persons Deprived of Liberty in Jails and National Penitentiaries which will be pilot-tested in Davao City.
Justice Peralta has been the Chairperson of the Third Division of the Supreme Court since September 2018, where he presides the deliberation of judicial and administrative matters assigned to the members of the said Division.
He has been the Chairperson of the House of Representatives Electoral Tribunal (HRET) since August 2018 where he used to be a member since 2011. Through his leadership of the HRET, which handles protest cases and quo warranto cases involving sitting members of the House of Representatives, all the cases that were filed during the 17th Congress were all decided before its term ended in June 2019. For a while, he has acted as Chairperson of the Senate Electoral Tribunal which decides cases involving sitting members of the Senate of the Philippines.
In spite of his numerous responsibilities as a Member of the Supreme Court, Justice Peralta makes it his professional and personal advocacy to conduct lectures on various procedural and substantive rules for the various stakeholders of the justice system. He regularly serves as a resource person of the PHILJA in the conduct of training seminars for newly-appointed judges, pre-judicature programs, and continuing legal education for court attorneys, government and private lawyers, among others, regarding the basic principles of and special issues on the Revised Guidelines for Continuous Trial of Criminal Cases, The Rule of Procedure on Small Claims Cases, plea bargaining in criminal cases, computation of penalties, as well as development and updates in Criminal Law and Criminal Procedure, Special Rules of Procedure on Environmental Law and the Intellectual Property Law, and other rules of procedure where he is either a Chairperson or Member of the Rules Committee.
Justice Peralta is married to Court of Appeals Associate Justice Fernanda C. Lampas-Peralta, a certified public accountant-lawyer, with whom he has four children: Attorney Dorothy, John Christopher, Timothy John, and John Isaac, who are all accomplished musicians.