Samu Gu told police he was looking at the ocean and telling his 2-year-old son sitting in the back seat behind him to also look at the ocean when his car crossed the center line of Kalanianaole Highway near Makai Pier at Makapuu last year and crashed into a mo-ped traveling in the opposite direction.

The mo-ped operator, Elizar Acorda, 23, of Kahuku, died from injuries he suffered in the July 3, 2011, collision.

Honolulu police said Gu, 30, of Waimanalo, tested positive for marijuana use.

The city prosecutor charged Gu in May with negligent homicide and operating a vehicle without a driver’s license.

He pleaded not guilty Monday in state court. His trial is scheduled for October.

Police said Gu was traveling northbound on Kalanianaole Highway when his sedan crossed into the opposite lane of traffic and crashed into Acorda.

Acorda was taken by ambulance in critical condition to Castle Medical Center, where he died two hours later.

He had not been wearing a helmet.

Acorda was among a group of six friends on an around-the-island mo-ped ride.

Two of the friends, one riding in front of Acorda and one behind him, told police they saw Gu’s car swerve into their traffic lane and crash into Acorda head-on.

Another friend said he saw Acorda fly into the air from the impact. He also said debris from Acorda’s mo-ped crashed into his mo-ped, sending him tumbling and skidding on the roadway for about 30 feet.

That friend, 29, went to Castle in good condition suffering cuts and scrapes on his left hand, back and both knees and elbows.