"Through experience I know when you are that age you can think I'm too good to crash but that's not true, you are not.
"It is about raising the awareness, people dying is very serious and making the right choices matters."
He said he focused on highlighting things that young people make poor decisions on.
He said they included driving with alcohol or drugs in your system, distractions like texting, distractions like driving with passengers on a restricted licence and driving a car that has no warrant.
Western Heights High School's Students Against Driving Drunk (SADD) will hold an awareness day on Wednesday which fits in with what Murphy talked about.
SADD committee member and Year 13 student Alana Duncan, 17, said 70 students at the school would paint their faces white and act dead for the day, only talking to teachers.
"This is to raise awareness about the 700 teens who have died on New Zealand roads."
She said they would also be writing facts in chalk body outlines around the school and placing crosses near the walkways around the school.