The late Independent MP from British Columbia who kept the Liberals in power in the spring of 2005 was offered a $1 million life insurance policy by the Conservatives in an attempt to win his vote, according to an upcoming book.

Chuck Cadman, who was battling cancer and died in July 2005, sided with the minority Liberals in the crucial vote on May 19, 2005, ensuring Canadians would not have to head to the polls for a summer election.

New details about what happened behind the scenes of that dramatic vote are recounted in Like A Rock: The Chuck Cadman Story, written by Vancouver journalist Tom Zytaruk.

The book is coming out March 15, but CBC News has obtained a copy.

If the elements of the story are true, the Conservatives' actions may amount to a criminal offence.

Under the Criminal Code of Canada, it's illegal to bribe an MP.

Cadman, a former Reform and then Canadian Alliance MP, was dying of skin cancer when the crucial vote on a budget amendment came up on May 19, 2005.

The Liberal prime minister at the time, Paul Martin, needed Cadman's vote to stay in power, while Stephen Harper's Conservatives needed the Independent MP's support to force an election.

Two days before the vote, Zytaruk writes, Cadman was visited by two Conservative party representatives — who are not identified — and presented with a list of enticements to rejoin the party before the vote.

A million-dollar life insurance policy was on the list, Zytaruk writes.

"That was on him, so that if he died I'd get the million dollars," Cadman's wife, Dona, is quoted as saying. "There was a few other things thrown in there too."

Dona Cadman said her husband was offended by the offers, the book says.

The only other person present at the meeting in Cadman's office was the MP's legislative assistant, Dan Wallace, who, Zytaruk said, "recoiled like a spring" when asked what happened that day.

"I believe Dona Cadman as the day is long," Wallace is quoted as saying. "She has no interest in fabricating anything."

Book says PM confirmed details

Stephen Harper is also quoted in the book, confirming some of the details.

Harper said his understanding of the offer to Cadman was that "it was only to replace financial considerations he might lose due to an election.

"I don't know the details," he's quoted as saying in the book. "I can tell you that I had told the individuals — I mean, they wanted to do it — but I told them they were wasting their time. I said Chuck had made up his mind he was going to vote with the Liberals."

Harper also confirmed the people who met with Cadman were "legitimately representing the party."

Martin visited Cadman personally, but the book says he made no offers to the MP.

At the critical moment, Cadman cast his vote with the governing Liberals.

With his support, the House voted evenly 152 to 152 on Bill C-48. That left Speaker Peter Milliken, who is a Liberal MP, to break the tie with a vote for the budget.

At the time, Cadman told reporters he was thinking of the needs of his constituents, but admitted there were "a lot of other things" to consider.

He died in July 2005 after a two-year battle with skin cancer.

On Wednesday, the Prime Minister's Office said Harper never directed anyone to make a financial deal with Cadman, and that when he first heard the story from Dona Cadman he had it investigated but nothing was ever confirmed.