How a Criminal Appeal Works

A criminal appeal is a request to a higher court to review whether the trial court made a legal error serious enough to change the outcome — not a second trial, and the appeals court will not hear new witnesses, reweigh credibility, or let you introduce new evidence. If you or a family member has just been convicted and are thinking about appealing, the single most urgent fact is this: the deadline to file a notice of appeal is short and strict, often measured in days, and missing it can permanently forfeit the right to appeal at all.

An appeal is a review, not a do-over

People sometimes assume an appeal means getting another chance to tell their side of the story to a new jury. It doesn't. The appellate court does not retry the case. Instead, it looks at what already happened in the trial court — the judge's rulings, the jury instructions, how evidence was admitted or excluded, and whether constitutional rights were respected — and asks whether a legal mistake occurred that was significant enough to require a different result.

An appeal generally cannot be used just because a defendant or family member believes the jury "got it wrong" on the facts, or disagrees with a sentence that was within the judge's normal discretion. Appeals succeed when there is an identifiable legal error: evidence that should have been suppressed was admitted anyway, a jury instruction misstated the law, the prosecution withheld favorable evidence, or a constitutional right was violated somewhere along the way.

The deadline to file a notice of appeal is extremely time-sensitive

The document that starts an appeal is called a notice of appeal. Courts enforce this deadline strictly — in many systems it is treated as jurisdictional, meaning if it is missed the appellate court can lose the power to hear the case at all; in others it is enforced just as firmly once the other side objects. Either way, a strong underlying legal argument will not save an appeal that is filed late.

In the federal system, a criminal defendant must file a notice of appeal within 14 days after entry of the judgment, under Federal Rule of Appellate Procedure 4(b). State deadlines are set by each state's own rules and vary — some are similar, others longer — but they are consistently short and consistently enforced. Do not assume you have weeks to decide. If a conviction has just happened, find out the exact deadline in that specific court immediately, ideally the same day, from the trial attorney, the court clerk, or a new appellate lawyer.

• Right now, if a conviction just occurred: ask the trial lawyer, in writing, whether they will file the notice of appeal or whether new counsel is needed; confirm the exact deadline with the court clerk rather than relying on memory; ask about appointed appellate counsel if cost is a concern (indigent defendants generally retain a right to counsel on a first appeal); and file the notice of appeal even before the full argument is ready — it's usually a short document that just preserves the right, with the detailed legal argument coming later in the briefs.

Building the record

Once an appeal is filed, the next step is assembling the record on appeal — the trial transcript, admitted exhibits, docket filings, and the judge's rulings. Appellate courts are generally limited to reviewing what's already in that record; if a lawyer never objected to something at trial, it can be hard or impossible to raise it for the first time on appeal. Preparing the record can take weeks or months, and briefing deadlines typically run from when it's completed, not from the date of conviction.

Briefs: where the legal argument actually happens

The appeal is argued primarily through written documents called briefs. The opening brief is filed by the person appealing (usually the defendant, called the "appellant"), laying out the specific legal errors claimed and citing the record and case law supporting each one. The prosecution (the "appellee") then files a response brief arguing why the trial court's rulings should be upheld, and the appellant may file a shorter reply brief addressing those points. Appellate judges typically read these briefs closely before any hearing, and in many cases the briefs — not a dramatic courtroom moment — are what decide the appeal.

Oral argument

After briefing, the court may schedule oral argument, where lawyers for each side appear before a panel of appellate judges (often three) and answer questions about the case. It's usually brief — often well under an hour — and focused on the judges' specific concerns, not a general retelling of the case. Many appeals, especially in busier courts, are decided without oral argument at all, based on the briefs alone.

Standards of review: why the type of error matters

Appellate courts don't review every issue the same way. The applicable standard of review determines how much deference the trial court's decision gets, and it often decides the outcome:

• De novo review: used for pure questions of law (for example, whether a statute was interpreted correctly, or whether police conduct violated the Fourth Amendment). The appellate court gives no deference and decides the question fresh.
• Abuse of discretion: used for many trial management and evidentiary rulings. The court will not reverse simply because it might have ruled differently — it asks whether the trial judge's decision was unreasonable.
• Clearly erroneous: used for a judge's factual findings (for example, in a suppression hearing). Substantial deference goes to the trial judge, who saw the witnesses firsthand.
• Harmless error: even a real legal mistake can leave a conviction standing if the court finds it did not affect the outcome given the strength of the other evidence.
• Plain error: if the trial lawyer did not object at the time, the appellate court will often review it only for "plain error" — a much harder standard, requiring an obvious mistake that affected substantial rights and the fairness of the proceeding.

This is why trial-level objections matter so much: a problem never objected to at trial is far harder to win on appeal than one preserved with a timely, specific objection.

What kinds of errors get raised

Common grounds include improperly admitted confessions (implicating the warnings required by Miranda v. Arizona, 1966), evidence from an unlawful search or seizure (the exclusionary rule from Mapp v. Ohio, 1961, and stop-and-frisk limits from Terry v. Ohio, 1968), and speedy-trial claims under the balancing test from Barker v. Wingo (1972). A separate, very common ground — often raised after the direct appeal, in post-conviction proceedings — is ineffective assistance of counsel, governed by the two-part test from Strickland v. Washington (1984): the lawyer's performance must have been deficient, and that deficiency must have actually prejudiced the outcome. Claims that the prosecution withheld favorable evidence are governed by Brady v. Maryland (1963).

What happens after the decision

An appellate court can affirm the conviction (leave it standing), reverse it (throw it out), or vacate and remand — sending the case back to the trial court for a new trial, resentencing, or a specific hearing. Losing doesn't necessarily end the road: many systems allow a further petition to a higher court (a state supreme court or the U.S. Supreme Court, though these are usually discretionary and rarely granted), or separate post-conviction / habeas corpus proceedings that can raise issues outside the original record, such as newly discovered evidence or ineffective assistance of counsel.

What to do if you're facing this

1. Find out the exact notice-of-appeal deadline in your court immediately — do not wait, and don't assume it matches what you've heard about a different state or case.
2. File the notice of appeal to preserve the right, even before every argument is fully developed.
3. Talk to a criminal appellate lawyer as soon as possible — appellate practice is a distinct skill from trial practice, and many trial lawyers refer appeals to specialists.
4. Ask about appointed counsel if cost is a barrier; the right to counsel can extend to a first appeal.
5. Keep every trial document — judgment, sentencing order, docket sheets — organized, since your lawyer will need them to order the record.

Frequently asked questions

Can I introduce new evidence on appeal?

Generally no. Direct appeals are limited to the existing trial record. New evidence — such as a witness recanting or newly discovered forensic results — is typically raised through a separate post-conviction or new-trial motion instead.

How long does a criminal appeal take?

It varies widely by jurisdiction and workload, but appeals commonly take many months to more than a year from filing the notice to a final decision, largely because of the time needed to prepare the record and complete briefing.

Do I stay out on bail during the appeal?

Sometimes, depending on the offense, the sentence, and the court's rules on release pending appeal — raise this with your lawyer right after conviction.

What if my trial lawyer missed the appeal deadline?

This can potentially be raised as its own ineffective-assistance claim, but those procedures and time limits are also strict — get a lawyer involved immediately rather than waiting.

Is an appeal the same as a pardon or expungement?

No. An appeal challenges legal errors in the conviction itself. A pardon is executive clemency, and expungement or record-sealing is a separate process that may be available later regardless of whether an appeal was filed.

This article is general legal information, not legal advice, and reading it does not create an attorney-client relationship. If you are facing a criminal charge or conviction, talk to a licensed criminal defense or appellate attorney about your specific deadlines and options.