An attorney representing the estate of a two-month-old baby who died from a viral infection of the heart told the state Supreme Court on Wednesday that the trial court’s jury instruction discussing the “error in judgment” rule reflected precarious legal terrain.

For Clifford A. Rieders, the problem with giving trial judges discretion as to whether they may use that instruction — which goes beyond the standard of care — teed up a landscape in which doctors could be exculpated despite negligence due to confusion among jurors.