OAKLAND, Calif. (CN) – Attorneys for a couple who claim Monsanto’s Roundup weed killer gave them both cancer tried to convince a California jury Thursday that the agrochemical company engaged in decades of fraud to hide the fact that the herbicide is carcinogenic.

Plaintiffs’ attorney Brent Wisner made explosive new allegations about the Bayer AG unit during opening statements in the joint trial of Alva Pilliod, 76, and Alberta Pilliod, 74, a married couple from Livermore, California, diagnosed with non-Hodgkin lymphoma four years apart who claim that their 35 years spraying Roundup on their residential properties gave them the disease.

“The product started in fraud and the evidence will show it is still going on today,” said Wisner, of Baum Hedlund Aristei Goldman in Los Angeles.

Alva was diagnosed with systemic non-Hodgkin lymphoma in 2011 and has been in remission since, after undergoing aggressive chemotherapy treatment that degraded his cognitive function, said Wisner.

Alberta was diagnosed with the same cancer in 2015 after doctors found a tumor in the middle of her brain. She was declared cancer-free in 2016 following a round of chemotherapy that left her with extensive brain damage, but relapsed the next year. A second round of treatment stabilized the tumor, and she is now considered in remission.

The probability that both Alva and Alberta would get non-Hodgkin lymphoma is 1 in 20,000, Wisner told the 12-person jury in Oakland on Thursday. Their treating physician said it was so unlikely they would both develop the same cancer that an environmental factor like Roundup was the likely culprit.

Wisner on Thursday ran through a list of Monsanto’s newly revealed alleged sins, starting with the so-called IBT scandal. The company seemingly planted one of its employees at a contract lab called Industrial Bio-Test Laboratories (IBT) in the 1970s to fake negative mouse carcinogenicity data for Roundup’s active ingredient glyphosate that were to be used to win regulatory approval for the weed killer in 1975; planned an attack to discredit the World Health Organization’s (WHO) cancer research agency, anticipating the agency would classify glyphosate as a probable human carcinogen in 2015; and exploited “deep connections” within the U.S. Environmental Protection Agency to classify glyphosate as non-carcinogenic.

Although the Pilliods’ case is the third case to go to trial alleging Roundup causes non-Hodgkin lymphoma, it is the first time a jury will hear some of the allegations to which Wisner alluded Thursday. Evidence of the IBT scandal was not presented in the previous two trials in San Francisco state and federal courts, where both juries found for the plaintiffs and awarded them tens of millions of dollars in damages.

Neither was a revelation that University of California at Berkeley toxicologist Luoping Zhang was “so outraged” by the EPA’s failure to follow its own herbicide-assessment guidelines that she recently resigned from an EPA glyphosate-review panel to conduct her own study of the chemical. That study, released this past February, found that glyphosate exposure increases the risk of developing non-Hodgkin lymphoma.

Wisner emphasized to the jury that Roundup does not come with a cancer warning on the label, nor does it instruct residential users to wear protective clothing or equipment while spraying it. Monsanto’s old television commercials meanwhile depicted consumers spraying Roundup in sleeveless t-shirts and shorts, leading the Pilliods to believe it was safe.

But Monsanto knew all along it wasn’t, Wisner said. The company has known for 40 years that Roundup causes tumors in rodents and for 20 years that it causes non-Hodgkin lymphoma in humans, but refused to include a cancer warning to safeguard the enormous profits generated by the most widely used herbicide in the world.

“This case is really about choice,” Wisner said, adding that the Pilliods insist they would not have sprayed Roundup had they known it causes cancer.

“You give the consumer the right to make a choice” about a chemical that “causes cancer before they buy it,” he said. “Because that failure means people get hurt, and they have to deal with the consequences. That’s how it works.”

Tarek Ismail, Monsanto’s attorney with Goldman Ismail Tomaselli Brennan & Baum in Chicago, didn’t directly address the new allegations in his own opening remarks Thursday, telling jurors only that the plaintiffs plan to take Monsanto’s apparently damning internal emails “out of context.”

And Ismail disputed that Roundup caused the Pilliods’ cancer. He began his argument by running through the Pilliods’ medical history, noting they both have several known risk factors for non-Hodgkin lymphoma. Alva has a history of skin cancer – he has been diagnosed with multiple forms of it 22 times – the autoimmune disorder ulcerative colitis, and five bouts of meningitis.

According to Ismail, autoimmune conditions like ulcerative colitis increase the risk of developing non-Hodgkin lymphoma. And meningitis is “an extremely rare condition” that weakened Alva’s immune system, he said.

“It is highly probative of having a weakened immune system, which put Mr. Pilliod at risk of” non-Hodgkin lymphoma, he said.

Alberta, meanwhile, had bladder cancer – which more than doubles the risk of non-Hodgkin lymphoma – and Hashimoto’s disease, a condition in which the immune system attacks the thyroid gland, which produces hormones that help coordinate the body’s functions. The condition, Ismail told jurors, triples the risk of non-Hodgkin lymphoma.

Ismail rounded out his remarks by noting that 100 countries have deemed Roundup safe to sell since the herbicide was developed in 1974. He added that regulators in the U.S., Canada and Europe re-reviewed glyphosate after the WHO’s cancer agency announced its findings and again concluded that glyphosate is safe.

“When you see the EPA’s determination,” Ismail said, “it is backed by solid science.”

Ismail closed by urging the jury to return a verdict based on the scientific evidence and not on sympathy for the Pilliods or distaste for Monsanto, which has long had a reputation for greed and deceit.

“This case is not a referendum on Monsanto,” he said. “You all confirmed that you were going to be able to put aside any compassionate feelings for the plaintiffs and any less compassionate feelings for Monsanto” to render a fair verdict.