The Bukyeong Jang-do case looks like there was organized protection by local police, similar to the Jang Yoon-gi case

Jang Yoon-gi also had protection from his parents who were police officers.
Looking at how they arbitrarily manipulated the Bukyeong Jang-do disappearance records, deleted CCTV footage, and erased call logs, it shows that this is how the Jeju police system operates normally.
Furthermore, given the local Jeju surnames and the nature of regional police organizations, there is a high possibility that many nearby officers are providing assistance.
Cases committed by local police should not be investigated by the local police themselves.
Even during the Goryeo and Joseon dynasties, regional corruption was investigated by the central government through officials such as:
Anchalsa (按察使) / Sasimgwan
Amhaeng-eosa (暗行禦史) / Gyeonggwan-chalsa
In modern times, with the advancement of decentralization, too much power has been concentrated in local regions, resulting in a system that puts citizens' lives at risk.
Corruption among local civil servants and police increases due to decentralization; is this really the right way to handle these matters?