Two of the four people on trial accused of a vicious attack on a Te Puna family have had their charges withdrawn.

In a turn of events on the third day of a four-day trial in Tauranga District Court Rihari Jarrod Borell, 28, was discharged on all four charges and allowed to walk free from court.

He was pleading not guilty to two counts of injuring with intent to cause grievous bodily harm and two counts of possession of an offensive weapon.

His sister Jasmine Hira Borrell, 25, was also discharged on two of the four charges she was facing in relation to the altercation at the Duncan's family home in 2012.

She pleaded guilty to the remaining two charges of assault on Matt Cooper and Steven Peter, who were friends of the Duncans and at the property on the night of the attack.

The judge remanded her on bail to reappear for sentencing on October 14.

The trial will continue for the two remaining accused - Derek Michael Drewery, 27, and Jack Simon Ake, 52.

Both are accused of being part of a group allegedly armed with spades and weapons that attacked Andrew Duncan and his family at a Te Puna home on the night of November 23, 2012.

In giving evidence yesterday Andrew described how he was woken up by smashing windows and his son yelling for help. He told the court he went outside and remembers an altercation with someone holding a bat, before he was knocked unconscious. Read more about the complainant's evidence here.

Ake is charged with injuring with intent to cause grievous bodily harm and wounding with intent to cause grievous bodily harm.

Drewery is facing one count each of injuring with intent to cause grievous bodily harm, wounding with intent to cause grievous bodily harm and common assault.

The trial is expected to conclude tomorrow.