He said the teen fell asleep at the wheel after staying awake the night before, and admitted causing the crash.
"It's freaked him out," the lawyer said.
"It is shocking for him and his family that he is before you now."
Judge Emma Smith declined bail, remanding the teen in custody without plea until his next appearance on November 15.
Legislation bars the publication of the defendant's name, any details that could lead to his identification or the names of the complainants.
The victims of the crash were part of a family convoy driving to Queenstown for a Labour Weekend day trip.
The women who died were in the same vehicle, family members said.
A brother of one victim said their wider whanau were "crushed" by what had happened.
A Givealittle appeal, set up by close friends of the women, described the second victim as ''the strongest and most resilient of mothers'' to her seven children.
The page said there were now ''two less beautiful, shining lights in this world''.
As of today, the fundraiser had reached nearly $15,000.
