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The Supreme Court issued an important criminal justice ruling on Thursday about the appropriate bounds of plea bargains. In an 8–1 opinion written by Justice Elena Kagan, the court held that some plea agreements that waive a defendant’s right to appeal a bad sentencing may lead to a manifest miscarriage of justice, and therefore can be declared void by courts. But while the 8–1 vote may make this case initially come across as noncontroversial, there are a series of disagreements between the justices, including among Donald Trump appointees, that could have a serious impact on the future rights of trial by jury.

The federal government charged a man named Munson Hunter with 10 counts of bank and wire fraud for a series of business transactions. As is often the case, the prosecutor hoped to get a guilty plea out of Hunter. The prosecution leveraged the sheer number of counts that they’d brought, saying to Hunter that they would drop nine of the 10 charges, which in total could combine to 300 years of jail time, if Hunter would plead guilty to one of the lesser offenses. Hunter agreed and signed a plea bargain.

The plea bargain contained a number of waivers. Most notably, Hunter agreed that he could not appeal the court’s ruling cementing his guilty verdict. Moreover, Hunter would not be able to appeal the sentencing that would happen after the plea was entered, meaning he would have to sign the plea agreement before knowing his ultimate sentence. The only area where his rights were explicitly retained was that Hunter could still appeal under a claim of ineffective assistance of counsel, which the Supreme Court had recognized as a constitutional right that could not be waived.

After he signed the agreement, something strange happened at Hunter’s sentencing. Instead of just receiving a sentence of about five years, the court also tried to impose a requirement that Hunter be required to start taking mental health medications........

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