Jurors have been told in B.C. Supreme Court that the officer charged in the deadly sinking of a B.C. ferry concocted an unbelievable story and that common sense says he is guilty of criminal negligence for not doing his job.

Navigation officer Karl Lilgert is on trial for two counts of criminal negligence after two people died when the Queen of the North ferry ran aground on March 22, 2006 and sank to the bottom of Wright Sound.

During closing arguments in Vancouver on Friday, Crown prosecutor Robert Wright told the jury Lilgert told a story that was "completely unbelievable, fabricated and concocted" about having to avoid a nearby vessel to cover up for the fact that he wasn't paying attention — and had missed a vital course alteration.

Wright pointed out that several witnesses testified the weather was actually quite good the night the ferry sank, not stormy as Lilgert testified, and the ship's navigational equipment was in good working order, not defective as Lilgert claimed.

Wright said the jury should ignore Lilgert's explanation of the moments before the ferry ran aground, as well as testimony from his former lover, quartermaster Karen Briker, who also testified Lilgert was actively navigating the ship.

Wright pointed to electronic records that showed the ship did not alter course for twenty minutes before the crash, saying that showed that Lilgert was not doing his job.

He said the jury didn't need to know what Lilgert was doing in the moments before the ship ran aground, because it was common sense to conclude that he was not doing his job, was negligent and should be convicted.

"We don't know what he was doing, but we know what he wasn't doing and that was his duty," he said.  

The judge is expected to issue his final instructions to the jury on Monday before the jury starts deliberations on the verdict.

With files from The Canadian Press