Denis told the legislature that publicizing details of the contingency agreement with International Tobacco Recovery Lawyers could harm their case by giving ammunition to the opponent.
The deal has come under fire in recent days because one of the firms is tied to Premier Alison Redford's ex-husband and political adviser Robert Hawkes.
Denis rejected demands from the Wildrose party to release the information.
"I'm on the side of everyday Albertans, not Big Tobacco," said Denis.
Wildrose critic Shayne Saskiw said the only way to judge the deal and the premier's role in awarding the contract is for the government to come clean.
"Will the premier stop blowing smoke, do the right thing and lay out the documents showing to us the agreement as well the (losing) offers put forward so Albertans can see for themselves whether they got a good deal or whether the premier awarded a super-lucrative contract to a friend?," Saskiw asked.
Deputy Premier Thomas Lukaszuk said the contingency agreement was negotiated by a third party and is the best deal possible.
"We as Albertans are paying the lowest contingency fee of any province that is involved in this lawsuit," said Lukaszuk.
The contingency deal will have the Tobacco Recovery Lawyers, or TRL, on the hook for all costs. TRL will only get paid a percentage if they win the suit.
Critics say they need to know the numbers, given that even just 10 per cent share could bring a $1 billion windfall to a law firm tied to the premier.
The opposition has been accusing Redford of misleading the legislature on her involvement in the case for a week, after the Wildrose and CBC presented documents relating to the decision retrieved under freedom of information legislation.
The documents referred to Redford, as justice minister in 2010, making the decision to pick to TRL. There is evidence that letters went out congratulating TRL on winning the competition and informing the other two competing firms that they had lost. All correspondence took place before Redford quit cabinet in February 2011 to run for leader of the Progressive Conservative party and ultimately become premier.
Redford unequivocally told the house during question period last week that she did not make the decision. She was backed up Verlyn Olson, her successor in the justice portfolio, who confirmed he made the decision to retain TRL and signed the contract in mid-2011.
Despite that, the Wildrose asked Speaker Gene Zwozdesky to formally sanction the premier for misleading the house. On Monday, Zwozdesky ruled that both sides made strong arguments but said that wasn't enough to find the premier guilty of such a serious parliamentary offence.
Nevertheless, the opposition renewed its attacks on Redford in the house Tuesday.
"How can the premier still claim she didn't make the decision?" said Wildrose Leader Danielle Smith.
"I think we're re-living last week," replied Redford. "I know what I was involved in. I know when the decision was made. I stand by my personal integrity and principles.
"I am proud of who I am."
Wildrose critic Jeff Wilson accused Redford of a double standard, ordering Gary Mar to step aside as Asia envoy earlier this year in a conflict of interest controversy but now refusing to step aside when she herself faces similar accusations.
Wilson reminded the house that Mar had been the favourite to replace Ed Stelmach as PC party leader and premier a year ago until Mar was beaten by Redford in party voting.
"Did you order Mr. Mar to step down just because most of your caucus chose to support him for leader and you wanted everyone to know who's boss?" asked Wilson.
Redford reclined in her chair, tilted her head back, looked at the ceiling for a second, shook her head, and stood up.
"Here's a response. I will not dignify that question with a response," she shot back.
After the Wildrose fired multiple questions, Liberal Leader Raj Sherman took up the cause, saying the premier should not have been involved in her ex-husband's file on any level.
"Premier, didn't you consider there would be at least the appearance of a conflict of interest?," said Sherman.
Redford replied, her voice rising to a shout at the end, emphasizing every word.
"There was nothing for me to recuse myself from because I! Didn't! Make! The! Decision!" she said as her fellow PC MLAs cheered.
The controversy has brought sharp exchanges between Zwozdesky and the opposition parties. They say Zwozdesky, a Progressive Conservative MLA, is broadly applying his rules as referee of the legislature to shut down legitimate questions on what the opposition calls "Tobaccogate."
On Monday, Zwozdesky surprised the opposition by saying he would not allow any questions on the topic because he was making a ruling on it. When the NDP asked for further clarification, he refused to give it.
"That is the end of that," he said.
All but one member of the Wildrose caucus then walked out of the house in protest. When they returned minutes later Wildrose member Gary Bikman broke parliamentary rules by holding up a handmade sign bearing the word "Shill", referring to Zwozdesky.
On Tuesday, a satirical hashtag #ZwozRulings grew in popularity on Twitter, with contributors trying to outdo one another on what they saw as other possible Zwozdesky-esque logic-defying edicts.
— War is peace, freedom is slavery, and proof is irrelevant.
— The "Godfather Part III" is the best of the trilogy.
— Rome WAS built in a day.
— You CAN get pregnant from a toilet seat.
There was a also a little John F. Kennedy: "Ask not what you can do for you province, but what the province can do for your family."
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