Mr Day said Tewao made a complete and utter fool of himself at the tangi last Friday, after turning up drunk and threatening marae and whanau members.
He said whanau members took offence to Tewao's actions and dealt to him.
"He's now sober and very remorseful," Mr Day said.
"He was overcome by grief and remorse and he probably shouldn't have been in the condition he was in on the marae. He wanted to pay his respects but completely lost the plot when he arrived. He drew his brother into it when threats were made.
"The whanau took huge exception to what he was on about and dealt to him ... he came off second best."
Tewao appeared in the dock with his hand heavily bandaged.
Judge Duncan Harvey said he was not surprised by the whanau reaction to Tewao's behaviour.
Judge Harvey said he did not condone people taking the law into their own hands, but he could imagine the whanau being upset by Tewao's actions.
He remanded Tewao on bail until August 19.
