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First Post-Durnell Monsanto Roundup Trial Begins In Missouri: Watch Gavel-to-Gavel via CVN

Posted by David Siegel on Sep 21, 2026, 9:15:19 AM

Brown closing-1

CVN screenshot of defense attorney Mike Brown of Nelson Mullins delivering his closing statement at the Durnell trial in 2023

Clayton, MO - Jury selection begins this week in Missouri state court at the first trial over Monsanto’s popular Roundup herbicide since a historic U.S. Supreme Court ruling held that many of the lawsuits pending against the agrochemical giant are preempted by federal law, and the full trial will be webcast gavel-to-gavel from opening statements forward by Courtroom View Network.

The Supreme Court sent shockwaves through the product liability world last June overturning a $1.25 million verdict awarded to plaintiff John Durnell in Missouri state court in 2023. The high court’s majority determined the Federal Insecticide, Fungicide, and Rodenticide Act preempts state law failure-to-warn claims, which often played a key role in lawsuits claiming exposure to the chemical glyphosate in herbicides like Roundup supposedly causes cancer.

The pending trial before Judge Brian May, with opening statements scheduled for September 29th, will be closely watched by both plaintiff and defense attorneys looking for a possible template for Roundup trials in a post-Durnell world. While previous Roundup trials dealt heavily with failure-to-warn claims under state law, the pending case will give attorneys a preview of a Roundup trials built entirely around design defect claims.

CVN’s gavel-go-gavel coverage will include both live and on-demand access to the proceedings, along with time-synced digital images of exhibits and demonstratives shown in the courtroom. Please email CVN for various subscription options ranging from access for one individual up to firm-wide institutional accounts for multiple viewers.

The trial takes place in St. Louis County just miles from Bayer-owned Monsanto’s former United States headquarters. Missouri courtrooms were a key vanue for Roundup trials before the Durnell ruling, with that trial (also recored by CVN) taking place just miles away in the City of St. Louis before Judge Timothy Boyer.

In addition to the Durnell trial, CVN recorded numerous other Roundup trials throughout the United States which are all available with a subscription to CVN's online trial video library. 

When the City of St. Louis jury first returned their verdict in the Durnell case plaintiff attorneys greeted it as welcome news, with the $1.25 million award ending a string of nine consecutive trial victories in lawsuits involving Monsanto’s popular herbicide.

Bayer promised an appeal at the time, likely not knowing this specific case would render failure-to-warn claims in thousands of other Roundup lawsuits moot along with likely impacting future mass tort litigation in state court involving products like pesticides and other herbicides.

The basis for Monsanto’s appeal of the Durnell verdict would eventually evolve into the opinion written by Justice Brett Kavanaugh that effectively end failure-to-warn lawsuits in state courts for thousands of Roundup plaintiffs and potentially countless more in other similar cases.

Given this pending trial’s unofficial status as a bellwether case for post-Durnell Roundup claims, both sides are bringing a phalanx of top product liability attorneys to Judge May’s Clayton courtroom.

The plaintiffs are represented by teams from Dallas-based Kirkendall Dwyer LLP and Washington, DC and California-based attorneys from Dovel & Luner LLP backed up by local Missouri counsel from The Simon Law Firm PC.

Monsanto is represented by local Missouri counsel from Husch Blackwell, along with pro hac vice counsel a large contingent of pro hac vice counsel from Sidley Austin LLP.

The multi-plaintiff case is captioned Theresa Aretino, et al. v. Monsanto Company, case number 20SL-CC03676 in Missouri’s 21st Judicial Circuit.

Email David Siegel at dsiegel@cvn.com

Topics: Missouri