Changi Prison raises tech bar with automated checks, surveillance system that detects fights

SINGAPORE: The deafening silence at Changi Prison on Thursday afternoon (Jun 21) was suddenly broken by a loud voice over the public address system. 

“All inmates, sit up straight. Look into the camera,” ordered a Singapore Prison Service officer, who works at Institution A4, the women’s prison. 

“All inmates, at ease,” she added, barely a minute later. 

The prison was testing what is known as an automated muster checking system, one of three new technological initiatives SPS is trialling as it moves towards automating work processes in prison – or what it calls a “prison without guards” concept.

Currently, muster checks are done manually by prison officers on the ground to account for inmates. The process has to be repeated a few times daily. 

SPS is trialling facial recognition technology to replace these manual checks. Cameras located in the cells would capture the facial images of inmates and verify them with the records in the database, SPS said. 

“Only discrepancies will be highlighted to prison officers for further verification, cutting down the time spent on manual checks,” SPS added. 

Superintendent Chan Kai Yuen, who is the senior assistant director at SPS’ transformation and technology division, told the media that the automated muster checks would make the process quicker. 

He explained that manual checks would typically take 20-30 minutes, but facial recognition allows the process to be completed in 10 minutes. 

Besides that, SPS is also trialling a human detection system known as Avatar. The system uses prototype video analytics to detect and alert prison officers to abnormal activities, such as fights, in cells. 

“Making use of video analytics, this surveillance system can detect acts of aggression using an algorithm that captures high intensity, erratic motions and various interaction points between two persons,” the agency said. 

Avatar is currently being experimented in a cell in a men’s cluster at Changi Prison. According to Mr Chan, the test has so far been “very promising”. 

“It has detected actual fights that occur in the cell. We are testing it in one cell now … when the technology is ready, we will introduce this to all cells,” said Mr Chan. 

He added that SPS is still ironing out “false alarms” that could be triggered when inmates are exercising, for instance. 

SPS is also trialling self-service vending machines that dispense items as varied as snacks and soaps.

This process is done by matching an inmate’s identity – via wrist tags embedded with electronic chips – with his weekly spending allowance. 

The cost of the items bought is automatically deducted from the inmate’s allowance. 

“This removes the need for officers to manually collate the inmate’s purchase orders, update their allowance account and distribute the canteen items,” SPS said. 

Commenting on all the three technologies that are being trialled, Mr Chan said it allows officers to spend less effort on routine, more labour-intensive activities and free up their time to focus on “higher order work” such as rehabilitation. 

“We can sit down and talk, interact and understand the inmate better … and help in charting a relevant rehabilitation programme,” he said. 

On top of the three systems being trialled, SPS has piloted an automated security equipment cabinet that allows officers to draw and return equipment safely, and a digital rehabilitation records management system that tracks inmates’ movements. Inmates are also able to access e-books and e-learning through shared tablets.