The federal judge overseeing multidistrict litigation over whether Monsanto's Roundup weed killer causes cancer is allowing a law firm that won a landmark California state court verdict to remain on the plaintiffs leadership team in the consolidated federal cases.

Over objections from Monsanto's lawyer, U.S. District Judge Vince Chhabria of the Northern District of California said at a hearing Thursday that he would allow lawyers from Baum Hedlund Aristei Goldman to remain on the plaintiffs steering committee. The firm and partner R. Brent Wisner had offered to step aside in the wake of a controversy surrounding publication of documents that Monsanto claimed were subject to a protective order in the case.

“My concern is about depriving the plaintiffs of lawyers who will do a good job examining and cross-examining the witnesses … who know the science,” said Chhabria at a hearing Thursday afternoon. “I'm going to reverse myself and allow your firm to remain in the leadership structure.”

However, Chhabria warned Wisner's partner, Michael Baum, that there would be “very, very severe sanctions and no warnings” if the judge were to find the firm engaging in any misconduct.

“On an ethical question, if you have even the slightest doubt take the conservative route,” Chhabria said.

Monsanto's lawyers at Hollingsworth LLP initially asked Chhabria last year to dismantle the entire plaintiffs leadership structure, which also includes lawyers from Weitz & Luxenberg, Andrus Wagstaff and The Miller Firm, after Wisner published 86 documents to his firm's website after a dispute over whether they should be confidential under a protective order in the case. The New York Times wrote a story based on the documents claiming that Monsanto had relied on scientific papers that it had ghostwritten itself to make the case that Roundup exposure didn't cause increased cancer risk.

After a testy hearing on the matter last year, Baum Hedlund and Wisner offered to step aside at the conclusion of an expert-heavy phase of the MDL. That so-called “general causation” phase involved a bench trial before Chhabria dealing with the basic question of whether plaintiffs could credibly show that glyphosate, the active ingredient in Roundup, causes non-Hodgkin lymphoma in humans at realistic exposure rates. In what the judge called a “very close question,” Chhabria in July allowed more than 400 federal cases to proceed by denying Monsanto's motion for summary judgment.

Less than a month after Chhabria's ruling, a San Francisco state court jury awarded $289 million to one of Wisner's clients—a former school groundskeeper who claimed he was diagnosed with terminal cancer after using Roundup as part of his job duties.

At start of Thursday's hearing, Chhabria playfully alluded to the state court verdict.

“Has anything happened in the state court since we last saw each other?” the judge asked, to a round of chuckles from the lawyers.

“Not that I can think your honor,” said Monsanto's attorney Eric Lasker of Hollingsworth, who noted that the case below was “not over.” (Monsanto's motions challenging the state court verdict are due Tuesday.)

Lasker, who along with a colleague from his firm, was outnumbered 17 to two by plaintiffs lawyers at Thursday's hearing, tried to persuade Chhabria to drop the Baum Hedlund lawyers, but was denied.

“They have lots of very fine attorneys here. I don't see why they can't manage the litigation with the firms that they have,” Lasker said.

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