Police have changed their alcohol policy for Armed Offenders Squad members to zero consumption within 12 hours of starting work.
An inquiry has found that 14 members of the squad of about 60 that responded to a callout, resulting in a fatal shooting, had consumed alcohol in the 24 hours before the incident.
In July last year, the AOS was called to Opunake in Tarakanki when Anthony Ratahi took his former girlfriend hostage.
Ratahi had just been released from prison and was known to be violent and dangerous. After a siege lasting 12 hours, he was shot and killed by an officer. An investigation found the shooting was lawful.
Police assistant commissioner of operations Nick Perry says the officer who fired the fatal shot had not been drinking.
Mr Perry says most of the officers who had consumed alcohol were involved in a police inner-security cordon only. He says officers felt they should be involved due to the critical nature of the incident.
Mr Perry says the police policy was ambiguous in relation to AOS staff not on standby and were being re-called for duty. The policy is now that any officers on such duty must not consume alcohol within 12 hours of beginning work.