HONOLULU -- Almost a year to the day after the disappearance of Masumi Watanabe, a jury was asked to decide if she was murdered.

For the jury in the murder trial of Kirk Lankford, the case boiled down to who you believe: the suspect, or the scientific experts who testified against him.

"Where is it in the evidence that Mr. Lankford killed anybody?" defense attorney Don Wilkerson told the jury.

Most of the best physical evidence, especially the body of Watanabe, Lankford testified that he disposed it. He said he disposed of the evidence to hide an accidental tragedy that threatened his job.

"He needed his job to support his family. He made a bad decision, but his bad decision was not murder in the second degree, his bad decision was not manslaughter," Wilkerson said.

"The reason Kirk Lankford did these terrible thing was to cover up the terrible crime he had committed," Prosecutor Peter Carlisle said.

Carlisle said the evidence suggested Lankford lured Watanabe into his truck then strangled her when something went wrong. He said Lankford's story about Watanabe throwing herself from his speeding truck defies both science and common sense, and that his glibness on the witness stand was evidence of lying.

"Remember that, how its like pulling teeth to get the truth out of this person," Carlisle said.

However, Lankford's attorney said the lies came from prosecution witnesses; especially the traffic accident expert who said Lankford's account was impossible.

"He came from the mainland to come over here and pull the wool over our eyes and tell us a story about what happened, and it's not true," Wilkerson said.

"Her death was the intentional and knowing result of the actions of Kirk Lankford and that in the state of Hawaii is called murder in the second degree," Carlisle said.

Besides not guilty or guilty of murder, the jury was also given the choices of manslaughter or murder by omission, which means they think Lankford injured her and let her die. It could take a full day for jurors to understand the instructions and organize thousands of pages of evidence.