NEWMARKET, Ont. - A former Toronto traffic cop accused of murdering his mistress wasn't acting as a "right-thinking member of society'' when he decided to seal Linda Mariani's corpse in a garbage bin rather than call 911 after she died from an accidental fall, his lawyer argued Tuesday.

But there's no forensic evidence to suggest Richard Wills, 50, should be held responsible for the woman's death, lawyer Raj Napal told the jury as closing arguments got underway in a high-profile trial in this suburban city north of Toronto.

Wills behaved in a "shocking'' and "alarming'' way following Mariani's death in February 2002, which he claims occurred when she accidentally fell down the basement stairs of his home, Napal acknowledged.

But he urged jurors to focus instead on the forensic evidence and put his client's bizarre decision to store the woman's body -- ostensibly to ensure the couple's burial wishes would be properly honoured -- out of their minds.

"He should not have put the deceased in a container, he should have called 911,'' Napal said.

"It was an error in judgment. The reality is the man lost all judgment at that moment.''

The Crown alleges Wills killed Mariani, 40, when she wouldn't leave her husband, first clobbering her with a baseball bat, then choking her with a skipping rope before stuffing her body into a garbage bin and hiding it behind a fake wall in his basement.

A bat and skipping rope -- the latter wrapped three times around Mariani's neck -- were found with the body when Wills led police to it four months after her disappearance in February 2002.

But Napal insisted the evidence -- including reports from both a pathologist for the Crown and another for the defence -- doesn't support the Crown's theory that she suffered a severe blow to the head.

If the mother of one did die according to the Crown's theory, she would have likely fallen forward and suffered facial injuries as well as a decompressed head fracture, he said.

"The fracture is absolutely inconsistent with a baseball bat,'' Napal said.

He also argued there's no forensic evidence to suggest Mariani was still alive when he dumped her headfirst into the bin, or that she died of asphyxiation.

"It's the same old hypothetical theory that the Crown has repeated again, which is not supported by the evidence,'' Napal said.

The defence argues Mariani fell down the stairs and struck the back of her head on the ceramic tile floor and was killed almost instantly.

During the sensational trial, Wills testified he hid Mariani's body out of a sense of panic.

He said he was worried Mariani's relatives would want to bury her in the family plot and not at his Wasaga Beach cottage property, where the couple had planned to be interred together under a secret lovers' pact.

"I loved her. I trusted her with all my heart. I still do,'' Wills told the jury when he testified in August, often appearing on the verge of tears as he described his family, his career, and the shame he felt over his secret nine-year affair with Mariani.

Wills has pleaded not guilty to a charge of first-degree murder.

As Napal began his remarks Tuesday, he told jurors they faced a huge task: deciding whether Wills is guilty of first- or second-degree murder. He appeared to forget to mention the not-guilty verdict that his client is presumably hoping for.

The haste with which Wills cleaned up his basement after Mariani's death does not suggest the death was premeditated, as he had to work that very day and was also expecting his children to drop by, Napal said.

Closing arguments are expected to continue through the week.