BAYER hopes of a smooth process settling thousands of the Roundup court cases lodged against it in the US have hit a road block. The agribusiness giant last month launched its plans to settle the majority of the cases in the US against it, alleging its glyphosate-based herbicide Roundup caused cancer, at a cost of $A15 billion. However, a US Federal judge has questioned whether the proposed Bayer deal would stand up legally. Vince Chhabria, federal district judge for Northern California, said moving the debate about whether glyphosate, the active ingredient in Roundup, from the judicial system to a panel of scientists may not be constitutional. He also said it may not be appropriate to lock in a scientific finding when the science surrounding the usage of the herbicide was evolving. The tone of Judge Chhabria's comments was ominous for Bayer, with the judge expressing concerns about the propriety and fairness of the Bayer proposal. In response, Bayer has agreed to withdraw the pending motion for preliminary approval of the parties' issue class agreement. A Bayer spokesman said the withdrawal will enable the parties to more comprehensively address the questions recently Judge Chhabria. A hearing on the matter was scheduled by Judge Chhabria for July 24. Bayer will also face opposition to the settlement from other quarters. Some plaintiffs with cases lodged have announced they do not plan to participate in the proposed settlement. However, the Bayer spokesperson said the company remained 'strongly committed' to a resolution that simultaneously addresses both the current litigation on reasonable terms and a viable solution to manage and resolve potential future litigation. "Mass tort settlements agreements like this are complex and may require some adjustments along the way, but the company continues to believe that a settlement on appropriate terms is in the best interest of Bayer and all of its stakeholders," the spokesperson said.