Donald Trump has vowed to appeal his conviction on 34 counts of falsifying business records. Some on the right have argued that the trial was a “target-rich environment” for an appeal. Others have said that the U.S. Supreme Court should “step in” and provide relief to Mr. Trump.

Nevertheless, the process will begin in New York, where state law gives Mr. Trump — and any other individual with a criminal conviction — an absolute right to an appeal before an intermediate appellate court known as the Supreme Court, Appellate Division, First Department.

As a prosecutor and a defense attorney for decades, I have argued hundreds of cases at this court. I’ve looked closely at the Trump case. The burning question now is, could his conviction be reversed on appeal? My answer is, the chances of that are not good.

Mr. Trump’s legal team can approach his appeal on several fronts, but only one, concerning the legal theory behind the falsifying business records charge, is likely to hold out anything more than the slimmest of hopes for the former president.

In recent years, the Appellate Division, First Department, has reversed appeals from criminal convictions in only about 4 to 6 percent of cases. These long odds should come as no surprise. While the Constitution guarantees criminal defendants a fair trial, it does not guarantee them a perfect one.

To warrant reversal of a jury’s verdict on account of an error, the appellate court must find that an error of some kind led directly to the conviction. A technical error that does not rise to that level is called a “harmless error” and will not cause a reversal of a conviction.