Someone other than Matthew Higa killed toddler Cyrus Belt before Higa threw the child in front of a delivery truck, defense lawyer Randall Oyama plans to argue in his closing statement in the Higa murder trial tomorrow.

A written version of Oyama's final argument alleges that the real killer may have been Shane Mizusawa, the boyfriend of Cyrus Belt's mother, or Clifton Higa, a friend of Mizusawa's who is not related to the defendant.

Mizusawa was watching the 23-month-old boy some 15 minutes before witnesses saw Higa throw the boy off a freeway overpass on Jan. 17, 2008, but there was no evidence or testimony in the trial about how Higa gained possession of the boy.

Oyama said in his written argument that one witness claimed to have seen Higa carrying a "cylindrical" package about two feet long when Higa walked to the overpass at the foot of Punchbowl shortly before noon.

The witness, Ryan Dahlberg, was working on a moped in a nearby garage and said he glanced at Higa as he walked past.

Dahlberg said he did not see Cyrus Belt, who lived in a nearby 'Iolani Avenue apartment with his mother, grandfather and Mizusawa.

Higa and his father, Shelton Higa, lived an upstairs apartment in the same building where Cyrus lived with his family.

Shelton Higa, Mizusawa and Nancy Chanco, mother of Cyrus, all testified at the trial that they regularly smoked crystal methamphetamine with each other and with Matthew Higa.

Another witness, Dahlberg's roommate Kraig Hengst, testified that he saw Higa throw the baby off the overpass and that the child "cartwheeled" in the air before disappearing from view as he fell to the freeway pavement 30 feet below.

Hengst said he believed Higa had thrown a "toy doll" from the overpass. A passenger in the truck that struck the boy, Jimmy Aliven, said he saw a "dead baby" pass in front of the windshield before the truck ran over the boy.

Oyama said the testimony of both witnesses is credible and supports his argument that the boy was dead or unconscious before Higa hurled him from the overpass.

"Both are describing a lifeless being," Oyama said.

Higa told police after he was arrested that Cyrus was alive, moving and crying before he was thrown to the freeway, but Oyama said that statement was not credible because of Higa's methamphetamine addiction.

Oyama said Circuit Judge Dexter Del Rosario, who presided over the nonjury trial, can either disregard witnesses who delivered "unbiased, consistent testimony with no history of mental problems" or disregard Higa's statement , which came from a man "with obvious mental problems who was under the influence of ice at the time."

Prosecuting Attorney Peter Carlisle's has not yet filed his closing argument.

Carlisle's case included testimony from Dr. Gayle Suzuki, deputy medical examiner, who said an autopsy showed Cyrus Belt died from wounds suffered in the fall to the freeway and from impact with the truck.

Oyama charged in his closing argument that Suzuki made her findings before being given all the evidence in the case, and that police withheld from her the statements of Dahlberg and Aliven.