Early career (1986–2012)

Dela Rosa joined the police force in 1986 as a Lieutenant of the now-defunct Philippine Constabulary^{[lower-alpha 4]} in Davao City.^[12] In 1992, he was designated as Chief Inspector and worked as one of the staff at Police Regional Office (PRO)-Davao. In 1997, he was designated as police provincial director of Compostela Valley.

In 1999, he was assigned to the office of the Police Director of the Philippine National Police (PNP) at Camp Crame in Quezon City. In 2001, he returned to PRO-Davao and continued his service as deputy chief of the Office of the Regional Personnel and Human Resource and Development Division (ORPHRDD) of Region XI. In 2003, he was promoted to Police Superintendent and was assigned to Camp Catitipan in Davao City. He was then transferred to the Directorate for Human Resources Doctrine and Development as head of training. In 2005, he was assigned to the Davao City Police Office (DCPO) as a city personnel officer. After eight months, he was transferred back to PRO-Davao and was promoted as chief of the Regional Intelligence and Investigation Division (RIID). In 2007, he became the director of the Compostela Valley Provincial Police Office (CVPPO) as its police chief. In 2008, he was promoted to a rank of Senior Superintendent. In 2009, he was moved to Davao del Sur where he served as director of the Davao del Sur Provincial Police Office (DSPPO). In 2011, he became the chief of the Regional Logistics and Research Development Division (RL-RDD) in PRO-Davao. In 2012, he was assigned to Davao City as the new director of the Davao City Police Office.^[2]

Davao City Police Office Chief (2012–2013)

Dela Rosa served as the chief of the Davao City Police Office from January 2012 to October 2013 under Mayors Sara Duterte (in office: June 30, 2010 – June 30, 2013) and Rodrigo Duterte (in office: June 30, 2013 – June 30, 2016).^[16][12] In 2012, he led the crackdown on the carnapping syndicate allegedly masterminded by Ryan "Baktin" Yu.^[17] In July 2013, he headed the successful rescue of the kidnapped Filipino-Chinese businesswoman Sally Chua.^[18][19] He also directed the implementation of Oplan Tokhang (Cebuano portmanteau for tuktok, "knock", and hangyo, "persuade") a campaign against illegal drugs where the police literally knock on the doors of suspected drug users and distributors and persuade them to cease their illegal activities;^[20] and Oplan Pakgang, (Cebuano portmanteau for “Pitulon ang Kabatan-onan sa Gang”, “Disciplining Youths in Gangs”) where the police, through a series of lectures and discussions, discouraged Davao City's youth from joining criminal gangs and other illegal activities.^[21][22]

Camp Crame (2013–2016)

After serving as Davao City Police Chief, Dela Rosa was assigned to the national headquarters of the Philippine National Police in Camp Crame where he worked for the PNP Intelligence Group from October 2013 to December 2014.^[4][12][23]

In 2015, Dela Rosa became a member of the PNP Board of Inquiry which investigated the Mamasapano clash that claimed the lives of 44 Special Action Force commandos, 17 Moro Islamic Liberation Front members and five civilians while the cops were on a mission to arrest international terrorist Zulkifli Abdhir, alias Marwan.^[24][25][26] Dela Rosa also served as the executive officer of the Directorate for Human Resource and Doctrine Development (HRDD).^[4][12][23]

A few days before the May 9, 2016, Philippine general election, Dela Rosa was relieved as brigade commander of the Reactionary Standby Support Force (RSSF) of the Philippine National Police allegedly due to his Facebook posts seen to be in favour of then-presidential candidate Rodrigo Duterte.^[27] However, Dela Rosa's commanding officer at that time, PNP deputy chief for operations Deputy Director-General Danilo Constantino, denied that Dela Rosa's Facebook posts were the main reasons why he was relieved of his duty. According to Constantino, Chief Superintendent Dela Rosa was relieved from the Reactionary Standby Support Force (RSSF) so that he could focus on his responsibilities as executive officer of the PNP Directorate for Human Resource and Doctrine Development (HRDD). Nonetheless, Constantino stated that the PNP Internal Affairs Service will investigate Dela Rosa's Facebook posts for possible administrative liabilities as the officers of the Philippine National Police are required to be neutral and apolitical during the elections.^{[28][29][30][31]}

On August 25, 2016, the newly appointed Chief of the National Police stated “You know who these drug lords are. Do you want to kill them? Kill them. It’s okay because you're the victim here.” “If you want, you know who these drug lords are. Go to their houses. Pour gasoline in their houses, set it on fire. Show them you’re angry,”^[32][33][34]

Rise to prominence as head police chief and BuCor director (2016–2018)

Dela Rosa was handpicked by then presumptive President Rodrigo Duterte as the new PNP Chief on May 19, 2016.^[13] On July 1, 2016, he was officially sworn in as the 21st chief of the Philippine National Police while being promoted to Director-General, the highest-ranked PNP officer.^[4] Amid Vice President Leni Robredo's criticisms of the Duterte administration's war on drugs, in October 2017, Dela Rosa said Robredo should set aside her alleged political ambitions to become president and advised her to "help Duterte first".^[35][36] Dela Rosa was set to retire on January 21, 2018, due to the mandatory retirement at age 56, but his term was extended for 3 months until April 21, 2018.^[37]

During his stint as PNP chief, Dela Rosa made the headlines regularly as he led the controversial drug war and Oplan Tokhang operations throughout the country.^[38] Several groups including human rights groups and religious leaders strongly objected Dela Rosa and President Duterte's initiatives. The controversy has been widely condemned for the number of deaths resulting from police operations and allegations of systematic extrajudicial executions including planting fabricated evidence to make it appear a suspected drug personality has possession of drugs and resisting arrest from authorities. The drug-related killings reached up to the United Nations Human Rights Council as it caused a death toll total of 12,000 according to reports of news organizations and human rights groups. In 2019, during his campaign, Dela Rosa took pride of it as it lessened the crime rate and resulted in millions of drug personalities surrendering to the authorities.^[39]

In May 2018, Dela Rosa was appointed as Director General of the Bureau of Corrections. He held the post from April 30, 2018, until October 12, 2018.^[40]

Senator (2019–present)