There are a few United States Supreme Court cases being decided this term that could have implications for criminal cases here in Maine.
One of the most important cases (Kansas v. Glover) concerns whether a person can be stopped in their vehicle when a police officer runs a license check and finds out only that the registered owner (not knowing anything else about the driver behind the wheel when the vehicle is seen by the officer) has a suspended license. In the case being decided, there was no other information that the driver of the truck was the owner, and he did not commit any kind of traffic infraction to be stopped either. The narrow issue to be decided then is whether the stop, only based on a license plate check and nothing else, violates the Fourth Amendment’s protection against unreasonable searches and seizures.
The case was argued in November and there has yet to be a ruling on that issue. The U.S. Supreme Court's opinion could also have implications about the use of automated license plate recognition technology. A ruling that overturns the Kansas Supreme Court (which suppressed evidence because the court said the stop was unreasonable) would enable police officers to simply pull someone over (which is a seizure, called a Terry stop) if they get a ‘hit’ – without also noticing a traffic infraction or any other reason for the stop or knowing who is behind the wheel. For context, since 2007, more than two thirds of state and federal cases it hears are overturned by the U.S. Supreme Court, so the odds are high that it will be.
As is always the case with constitutional law, the issue is less about the case's facts and more about wider implications. In the above case, the driver was the suspended owner. No harm no foul, you say? However, if you happen to be driving a car you have borrowed (or just bought from someone else), and the registered owner has a suspended license, a decision in this case that allowed the stop at issue (overturning what Kansas' highest court decided) would mean you are also being pulled over for that reason alone. That said, a police officer only has to follow you for long enough to have a reason that you are committing a violation (in Maine, officers are given statutory authority to pull someone over for a civil violation that only warrants a ticket), but the slow creep of additional government power to intrude on you by restricting your liberty (albeit briefly by forcing you to submit to an officer's authority) by stopping you when you are in a vehicle would continue. The erosion of the Fourth Amendment's protections is like a boiling frog. I also like to compare to a Swiss cheese of exceptions - now with more holes than actual cheese. Those protections affect everyone - not just those accused of offenses.
It is worth noting too that federal constitutional law is merely the floor below which states cannot go. Many states give their citizens further protections from government intrusions that are better than federal constitutional law. In this case, if it is kicked back down to the state, Kansas could adopt this stance and rely on its own state constitution to uphold its ruling, should the U.S. Supreme Court interpret the federal Fourth Amendment a different way. In the case of Maine, the Supreme Judicial Court, sitting as the Law Court, has repeatedly said the state’s constitutional provision about unreasonable searches and seizures (Art. 1, Section 5) gives no greater protections than its federal equivalent, the Fourth Amendment. This is a blunt way of putting it, but this has the effect of subcontracting citizen protections in Maine to the federal government by choosing not to raise the floor of what is impermissible government action any higher than what federal courts and the U.S. Supreme Court decide. See this law review article that discusses the issue further (and advocates for Maine to improve protections as other states have done) if you are interested - but it is quite a nerdy issue, admittedly.
Another Kansas case (Kahler v. Kansas) could also open a door to Maine legislators if they are ever intend to get rid of the insanity defense. Insanity is still a defense in Maine. It relates to the ability of a defendant to act with a criminal mind. The question the court will answer is whether getting rid of the defense violates the Eighth and Fourteenth Amendments. This case was argued in October last year.
Other cases that are less relevant relate to how criminal convictions or admissions are interpreted under federal immigration law, offenses under federal criminal law, whether a defendant can be convicted by a majority verdict (not the case in Maine), or whether New York was constitutionally able to severely restrict handgun possession to a person's house or visits to and from a gun range.
Decisions of the United States Supreme Court are released before June when the term ends. There is also the possibility that other cases, not listed here, could be put on the docket for a decision. If there are, they will be posted.