Improved safety measures are being trialled by the Ministry of Social Development at sites in Wellington and Levin, following the fatal shooting of two staff members in 2014.
Peggy Noble and Leigh Cleveland were shot dead by Russell Tully at Work and Income's Ashburton office, and he was sentenced to life imprisonment and ordered to spend at least 27 years in jail for their murders.
The ministry is now being prosecuted by WorkSafe for breaching the health and safety of the two women who died. It has pleaded guilty but disputed some facts.
The Wellington District Court was today shown a 3D depiction of the new safety measures.
Ministry of Social Development health and safety manager Melissa Gill said the measures included having two guards at the entrance to all Work and Income offices, one of whom would speak to clients before they entered the building.
The second guard would be inside, operating the door, and would also be able to scan inside and outside the building to detect potential threats, she said.
Eighty percent of threats to ministry staff were verbal, with only 1 percent of security alerts involving an actual assault. The new measures were designed to deal with the latter, Ms Gill said.
The ministry had considered the use of anti-jump wires on interview desks - similar to those used by some banks - but testing at the trial sites showed they would not be suitable.
"There was considerable unease from clients about their ability to work with case managers while looking through a wire barrier. During testing it was ruled out, as we couldn't deliver our services appropriately to clients using the wires in between the two."
Other safety measures included transparent material in interview pods, allowing staff a line of sight through the length of the office, duress alarms on every desk, and exit routes for staff from the front office to safe areas.
The safety measures could also be strengthened further, with the use of bullet-proof glass between clients and case managers.
There were several other factors to consider before the measures could be implemented nationwide, including cost and how to deliver services during any security upgrade, Ms Gill said.
A business case for the changes was being developed and would be taken to Cabinet so they could be signed off and implemented nationwide, she said.
The defence evidence concluded today, and Chief District Court Judge Jan-Marie Doogue gave both sides time to make written submission before she gave her decision.