A man accused of dangerous driving causing death testified Monday that he thought he had given Copper Island plenty of clearance as he navigated his way from Blind Bay at night.

What Todd Kerr thought he knew and what he might reasonably be expected to know under the law were key considerations as the case wound down in B.C. Supreme Court.

Kerr and friends were returning to a houseboat at Nielsen Beach on the north side of Shuswap Lake, late on Aug. 2, 2008, when their powerboat collided with the island. One of the boat's passengers was killed in the accident.

Under cross-examination by Crown prosecutor Neil Flanagan, Kerr told the judge he was unaware there was an island off the entrance to Blind Bay though he'd made two prior trips to the area. As an experienced boater, though, he said he knew boating at night can be tricky.

Kerr said he told his friend Jason Baird, the boat's owner, that he was concerned about a plan to head out on the lake to pick up two others.

"I didn't think this was a good idea … because it was getting very dark," he said. He said he didn't know there wasn't a spotlight on board until they were underway.

Baird was piloting the boat when they arrived at the lake while Kerr was stowing gear in the cuddy cabin below. Kerr said he couldn't recall his friend mentioning an island. Early in the fatal trip, the two traded places at the wheel since Baird was having trouble seeing.

A bench warrant was issued for Baird to appear in court as a witness, but he has not come forward.

Instead of the half-hour Baird estimated for the round trip, they spent about 40 minutes just looking for the pickup point, Blind Bay. There is a green flashing beacon on Copper Island, but it's not visible on eastern approaches. Kerr said he spotted the beacon headed into Blind Bay, then used it to help navigate his way back.

At one point, Kerr stopped the boat while the two discussed which direction they should take. Kerr, who denied having a heated exchange with Baird, stayed his course. He said he called his friend an idiot at that point, not the other way around as one passenger testified.

"You pushed that throttle forward in a mood of extreme annoyance and anger," Flanagan asserted. "That is why you collided with the island."

"Water off a duck's back," Kerr replied, referring to the coarse and derogatory banter in which the two would routinely engage. He maintained he wasn't angry.

Kerr said he felt confident he was on track, returning the same way in which he'd come. The collision occurred shortly after he'd brought the vessel up to planing speed, a safe speed since it allows the operator to see over the bow.

In his closing remarks, defense counsel James Sutherland argued a legal principle he said ought to be a foremost factor in assessing Kerr's criminal culpability. Conditions and standards differ from those of operating a motor vehicle, he noted.

"There must be some evidence the accused was aware of the standard before he can be found liable," Justice Robert Powers said, summarizing the defence position.

Noting that night navigation is permitted, Sutherland said his client used experience, care, proper judgment of the available aids, safe speed and visual checks to guide the craft.

"In other words, in difficult conditions, Mr. Kerr made a misjudgment, a navigational error."

Crown makes its closing admissions Wednesday.