He is one of the members of Hong Kong Police’s National Security Department, which is responsible for mass surveillance on citizens, arresting and prosecuting freedom fighters and activists in Hong Kong.

On May 2021, he was found visiting an unlicensed message center which was suspicious of providing sex service. As a result, he was transferred to the HR and Training Department.

他為香港警察國家安全委員會（下稱國安處）的其中一名成員，負責監控香港市民、檢空及囚禁支持自由的抗爭者。

於2021年5月，蔡展鵬被發現光顧涉嫌提供性服務的無牌按摩店，因此被調往人事及訓練科。