Former Minneapolis police officer Derek Chauvin is appealing his convictions for second-degree felony murder, third-degree murder and second-degree manslaughter in the killing of George Floyd. Could the outcome in one of the biggest trials in Minnesota history be overturned in the appeal process?

Even in cases that seem "open and shut" there are chances for legal success in appeal.

To begin with, Chauvin's conviction for third-degree murder will undoubtedly be reversed — due to the recent Minnesota Supreme Court decision in State v. Mohamed Noor.

In that decision, the court determined that third-degree murder does not apply in situations where a defendant aimed his actions at only one person. Noor, a former Minneapolis police officer like Chauvin, was convicted of third-degree murder in the shooting death of Justine Ruszczyk Damond. The court overturned that conviction, finding that third-degree murder, as a matter of law, only exists when a defendant "evinces a depraved mind" toward more than one person.

Because Noor's actions focused on a single individual, the court reasoned, he could not be convicted of third-degree murder.

Chauvin's actions focused only on Floyd, so his conviction on that third-degree murder charge will be reversed.

Second, Chauvin's conviction for second-degree felony murder lacks proof of a completed and separate underlying felony assault. Minnesota law states that a defendant is guilty of second-degree felony murder when they commit an intentional serious felony against a victim and the victim dies as a result.

Typically, when this crime is charged the resulting death is not only unintentional, it is unusual or unexpected.

In Chauvin's case, the state argued that the felony was Chauvin's third-degree assault on Floyd which caused Floyd "substantial bodily harm." Prosecutors argued that Chauvin caused Floyd to become unconscious, which by legal definition is substantial bodily harm, and that this unconsciousness caused Floyd's death.

Obviously, they prevailed on this argument since the jury found Chauvin guilty of second-degree felony murder, but they may not prevail on appeal because the evidence purporting to prove Floyd's unconsciousness is insufficient.

Chauvin's attorney could argue that the evidence at trial failed to prove whether Floyd lost consciousness for a period of time before he died or if he simply died. A human being does not necessarily lose consciousness before dying and may remain conscious right up until death. In Chauvin's trial, the state relied on numerous medical experts who testified that Floyd died of cardiopulmonary arrest — his heart and lungs stopped. But no expert testified that Floyd was unconscious for a period of time, and therefore had suffered a third-degree assault before he died, as opposed to dying in a single medical event.

The primary medical expert, Dr. Martin Tobin, testified specifically on this issue. He methodically walked the jury through the repulsive video showing Floyd under Chauvin's knee and very clearly explained the precise point when Floyd died. Referring to the video, he told jurors that they could see "one second he's alive and one second he's no longer."

He said, "you can see his eyes … he's conscious and then you see that he isn't. That's the moment the life goes out of his body."

Dr. Tobin never testified that Floyd lost consciousness for any period of time before he died and that the loss of consciousness caused or contributed to Floyd's death. The law requires this additional step.

Interestingly, the underlying felony issue was not addressed by the judge or defense attorney at trial, but on appeal it could be a critical issue. Right now, it is not included in Chauvin's list of 14 grounds for appeal.

Should Chauvin prevail on having the top two convictions reversed, only the second-degree manslaughter conviction would remain. It's likely to be upheld, because the state presented ample evidence that Chauvin created an unreasonable risk and consciously took a chance of causing Floyd's death, which meets the requirements of the charge.

While the Chauvin appeal will likely take a year to navigate the state appeals process, it's a case to watch. Like Mohamed Noor, Chauvin could be on the path to a significantly reduced state sentence.

Joseph Tamburino, of Minneapolis, is an attorney.