By Carey Gillam

Let the battle begin.

Opening statements are slated for Monday in the landmark legal case that for the first time puts Monsanto and its Roundup herbicide on trial over allegations that the company's widely used weed killer can cause cancer.

Dewayne "Lee" Johnson, a San Francisco-area school groundskeeper who used a form of Roundup regularly at his job, will face off against the global seed and chemical giant in a trial expected to extend into August. Johnson hopes to persuade a jury that Monsanto, which last month became a subsidiary of Bayer AG, is to blame for the non-Hodgkin lymphoma that doctors have said leaves him only weeks or months left to live.

Hints of the courtroom drama to come unfolded over the last week of June as jury selection dragged on for days, with Monsanto claiming widespread bias among prospective jurors. A number of the members of the jury pool, Monsanto's attorney said, revealed in jury questionnaires that they view Monsanto as "evil." Some even said they believe the company has "killed people," a Monsanto attorney lawyer told San Francisco Superior Court Judge Suzanne Bolanos.

Monsanto's attorneys cited similar issues in seeking to quell media coverage of the trial, telling the judge that she should not allow news cameras to televise the events because the publicity would "create a significant safety risk" for Monsanto's employees and attorneys who have been targeted with "multiple threats and disturbing communications," related to the litigation. Monsanto said employees have received threatening phone calls as well as ominous postcards sent to their homes. One postcard displayed a skull and crossbones along with a photo of the recipient, Monsanto said in a court filing.

Judge Bolanos ruled that some parts of the trial will be allowed to be broadcast, including opening statements, closing arguments and the announcement of a verdict. The trial is expected to be closely followed by people around the world; the French news outlet Agence France Presse is among the contingent of media who sought permission to cover the case.

Heated debates over the safety of Roundup and the active ingredient glyphosate have spanned the globe for years. Concerns mounted after internal Monsanto documents came to light through court-ordered discovery, showing conversations among Monsanto employees about "ghost" writing certain scientific papers to help influence regulatory and public opinion about Monsanto products.

Many of those internal corporate records are expected to be a key part of Johnson's case. Johnson's attorneys say they have evidence that Monsanto has long known that glyphosate-based herbicides such as Roundup are carcinogenic and have hidden that information from consumers and regulators. They allege Monsanto has manipulated the scientific record and regulatory assessments of glyphosate in order to protect corporate glyphosate-related revenues. Monsanto knew of the dangers and "made conscious decisions not to redesign, warn or inform the unsuspecting public," the Johnson lawsuit claims.

If they can convince a jury of the allegations, the lawyers say they plan to ask for potentially "hundreds of millions of dollars."

Johnson's lawsuit against Monsanto makes him one of roughly 4,000 plaintiffs who sued the company after the International Agency for Research on Cancer (IARC) classified glyphosate as a probable human carcinogen in March 2015. The IARC classification was based on a review of more than a decade of published, peer-reviewed scientific studies analyzing glyphosate and glyphosate-based herbicides. Johnson's case is the first to go to trial. Another is scheduled for trial in October in St. Louis, Missouri.

Monsanto argues there is no justification for any of the claims, and asserts it has decades of regulatory findings of safety and hundreds of research studies to back its defense. "Glyphosate is the most tested herbicide in history," Monsanto stated in its trial brief.

The company says it plans to introduce expert testimony demonstrating that the science is firmly on its side—"the entire body of epidemiology literature shows no causal association" between its glyphosate-based herbicides and non-Hodgkin lymphoma, the company states. As well, the animal testing database "is most consistent with glyphosate not being a human carcinogen," according to Monsanto.

The company's attorneys also plan to show that Johnson's exposure was minimal, and notably, that development of his type of cancer—a disease called mycosis fungoides that causes lesions on the skin—takes many years to form and could not have developed in the short period between Johnson's exposure and his diagnosis.

Monsanto's attorneys argue in court filings that Johnson's claims are so weak the judge should instruct the jury to provide a directed verdict in Monsanto's favor.

But Johnson's attorneys plan to tell jury members that Johnson began to experience a skin rash not long after being accidentally doused in a Monsanto glyphosate-based herbicide called Ranger Pro. He saw the rash—which turned to lesions and then invaded lymph nodes—worsen after he would use the chemical, which was frequently as he treated school grounds. Johnson's attorneys plan to tell jurors that Johnson was so worried that the herbicide was to blame that he called Monsanto's offices as well as a poison hotline number listed on the herbicide label. Monsanto employees recorded his outreach and his concerns, internal Monsanto documents show. But even after the IARC classification of glyphosate as a probable carcinogen, Monsanto did not inform him of any risk, according to evidence to be presented at the trial.

As part of their case, Johnson's attorneys intend to present video depositions of 10 former or current Monsanto employees, and of former Environmental Protection Agency official Jess Rowland, whose relationship with Monsanto has sparked allegations of collusion and an inquiry from the EPA's Office of Inspector General. They also will call to the stand Johnson himself, his wife, his doctors, and several scientists as expert witnesses.

The Monsanto witness list includes 11 expert witnesses who will testify both about the necessity of herbicides, including glyphosate-based herbicides; certain scientific literature; the plaintiff's type of cancer and potential causes; and other evidence that Monsanto says discredits Johnson's claims.

Johnson's attorneys will start the opening statements on Monday, and have projected that initial explanation of their case to the jury will take roughly 1-1/2 hours. Monsanto's attorneys have told the court they expect their opening statements to take roughly 1-1/4 hours.

Carey Gillam is a journalist and author, and a public interest researcher for US Right to Know, a not-for-profit food industry research group.