An Oklahoma judge is expected to rule Monday in the first state case to go to trial accusing an opioid drugmaker of being responsible for the devastating consequences arising from addiction to the powerful painkillers.

Cleveland County District Judge Thad Balkman is scheduled to deliver his judgment in open court at 3 p.m. The case is at the forefront of a wave of similar lawsuits by states, cities, counties and Indian tribes against drug companies over the wreckage caused by the national opioid crisis.

Oklahoma Attorney General Mike Hunter has called consumer products giant Johnson & Johnson, the last remaining defendant group in the case, a "kingpin" company that helped fuel the most devastating public health crisis in the state's history.

Before the six-week trial started in late May, Oklahoma reached a $270 million settlement with OxyContin-maker Purdue Pharma and an $85 million deal with Israeli-owned Teva Pharmaceutical Industries Ltd.

"The judge will probably find in favor of (Oklahoma), but will decline to give it a huge damage award, particularly since Purdue, the real bad boy in all of this, was able to cap its liability at the relatively modest sum of $270 million," said University of Kentucky law professor Richard Ausness, who has written extensively about opioid litigation. "Whatever happens, the losing side will probably appeal, so the matter will drag on for several more years."

Attorneys for Oklahoma outlined a plan developed by state mental health and addiction specialists to abate the opioid crisis that would range between $12.6 billion for 20 years or $17.5 billion over 30 years. Attorneys for Johnson & Johnson say that estimate is wildly inflated and claim the state is trying to hold the company liable for damages without any evidence that it caused the crisis.

"Throughout trial our team repeatedly laid waste to the state's case, which it built on misstatements and distortions," John Sparks, local counsel for Johnson & Johnson and its subsidiary, Janssen Pharmaceuticals, Inc., said following closing arguments. "The facts are that Janssen appropriately provided essential pain treatment options to Oklahomans while balancing the inherent risks associated with these medicines."

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