The attack caused a significant injury to the victim, he said, and could have been a lot worse. "People die from these sorts of punches."
Laungaue was ordered to do 175 hours of community work and 15 months of intensive counselling.
Louise Harvey, whose son Blair was killed by Laungaue in 2004, said news of the reoffending and reaction by the court was "a slap in the face".
"You're kidding me ... that's absolutely criminal," she said when told of the recent sentence.
Mrs Harvey said she attended all Laungaue's parole hearings and was convinced he remained unreformed. "It's proven that I wasn't just being a bitter old bitch. The justice system has fallen over totally."
In October 2004, Laungaue and brothers Siosifa and Sefanaia Tupou were kicked out of a Mangere property after becoming rowdy during a gin and drug binge.
Neighbours were concerned by their behaviour and called police, while Blair Harvey armed himself with a sword and confronted the trio.
The Tupous kicked and punched Mr Harvey while Laungaue wrestled the sword off him.
Mr Harvey staggered down a driveway but they pursued him; Laungaue swung the sword at him and it plunged into his left eye socket and through his brain.
The then 19-year-old was charged with murder. A jury trial found him guilty of manslaughter.
Justice Mark Cooper jailed Laungaue for 8 years. The Parole Board has confirmed he served the entire sentence.
After his release, Laungaue got caught up in a methamphetamine ring run by drug kingpin Zebulin Mario Davoren, whom he met in jail. Laungaue, then 30, was described by Justice Kit Toogood as a "general gofer" who was not heavily involved in the overall offending.
A report on Laungaue revealed his time inside had seen him struggle to adapt to his new-found freedom.
"As a result you could no longer relate to many of your old friends and those who understood you best were friends you made in prison," Justice Toogood said.
The judge said it was "troubling" Laungaue was assessed as having a high risk of reoffending and of causing harm to others.
He sentenced him to four months of home detention rather than jail.
Victims' advocate Ruth Money described Laungaue's latest sentence as "a joke".
But Otago University law professor Mark Henaghan said judges were obliged to look primarily at the facts of the case in front of them, rather than base their decisions on previous behaviour.