Notably, he is the president of Retired Personnel of the Royal Brunei Police Force Association (POLSARA).

[1] Hasrin received a diploma in police science from the National University of Malaysia after graduating.

[2] In advance of their meeting with the Ministry of Communications on 26 November 2018, a LegCo delegation led by Pehin Hasrin paid a working visit to the Land Transport Department (JPD) headquarters in Beribi on 14 October 2018, to observe the department's functions and public services and to familiarise themselves with problems came across in the nation's land transportation initiatives.

[3] Pehin Hasrin headed the Brunei delegation to the 42nd ASEAN Inter-Parliamentary Assembly (AIPA) from 23 to 25 August 2021, where he emphasised the need of harmonisation, cybersecurity, and digital inclusion for global resilience and gender equality, as well as ASEAN's solidarity in times of crisis.

[6] On 3 January 2013, He received the DUBC from President Tony Tan at a ceremony conducted in the Istana for the outstanding cooperation of the two police forces which has resulted in enormous operational successes for both nations in the fight against transnational crime and terrorism.