We refer to Mr Anthony Dass's letter (Why was security guard cleared despite criminal record?; March 20).

The Police Licensing and Regulatory Department (PLRD) screens all security officers to determine their suitability for a security officer licence. This includes a person's criminal records.

The licence is valid for five years.

Rajagopal Murugan had not come to PLRD's attention for secret society links when he last renewed his security officer licence in 2014.

Following his conviction last year, action has been taken to revoke his licence.

Superintendent Simon Ng

Assistant Director (Public Communications Division)

Public Affairs Department

Singapore Police Force