Committee hears bill to restore pre-2023 medical‑malpractice standard following Montana Supreme Court ruling

The House Business and Labor Committee heard testimony on House Bill 342, introduced by Representative Bill Mercer (House District 52, Billings), a measure that would codify Montana’s longstanding pattern jury instruction for medical‑malpractice cases and narrow the use of a proportionate‑risk jury instruction introduced by the Montana Supreme Court in 2023 in Kamen v. Glacier Eye Clinic.

Supporters told the committee the bill would restore a reasonableness‑based standard of care determined by medical experts rather than allow juries to apply a “proportionate duty” instruction that, they said, can cause juries to weigh a single catastrophic risk above competing clinical judgments.

Representative Bill Mercer, sponsor of the bill, told the committee the measure “is designed to say we are ... want to codify the standard of care that was in place before this Cayman decision.” Mercer said the bill aims to “put the law back where it was,” restoring the pattern instruction that has guided Montana medical‑negligence trials for decades.

Proponents emphasized the role of expert testimony in defining the standard of care. Amy Grimales, partner at the Crowley Fleck law firm, told the committee, “House Bill 342 simply reestablishes that the standard of care for medical malpractice cases is what a reasonable person would do. And that care is established by expert testimony.” Several hospitals, medical associations and physician witnesses joined in supporting the bill; speakers said the Supreme Court’s instruction was novel in the medical‑malpractice context and would encourage defensive medicine and reduce physician retention, especially in rural areas.

Physician testimony described clinical tradeoffs that, proponents said, are best evaluated by clinicians and experts. Nathan Allen, a practicing emergency physician, said clinicians routinely balance probability and severity of multiple concurrent risks — for example, weighing the benefits and bleeding risks of thrombolytic therapy in stroke — and that those judgments are what expert testimony and a reasonableness standard are meant to inform. “This calculation is what makes up the art and science of medicine, and it’s assessed by the standard of care,” Allen said.

Opponents told the committee the Supreme Court did not mandate the proportionate‑risk instruction in every medical‑malpractice trial and argued the instruction can be appropriate in particular cases. Hal Smith, identifying himself as representing the Montana Bridal Lawyers Association, described the reaction to the court’s decision as “an overreaction,” and said the pattern instruction will still be used in most trials. Trial lawyer Justin Stalpes (spelled in the record s t a l p e s) said both instructions may be given and that courts and juries have handled such instructions in other states.

Committee members questioned witnesses on practical effects and precedent. Representative Seekins Crowe asked whether failing to codify the prior instruction could lead to different jury instructions in different cases; Mercer pointed to Justice Baker’s concurrence in the Supreme Court opinion and said the bill would reduce inconsistent outcomes and preserve expert‑driven determinations of standard of care.

The committee closed the hearing after roughly one hour of testimony from clinicians, trial lawyers and hospital representatives. The committee did not take executive action on House Bill 342 during the session; the clerk later noted HB 342 was among the bills the committee had heard but not acted on and would remain in the committee folder pending a future transmittal date.