How the Criminal Appeal Process Works | Brownstone Law

In This Blog, You’ll Learn How the criminal appeal process works, from filing a Notice of Appeal to receiving the final decision. Who can appeal a conviction in a criminal case, and how does the whole process work? The most common grounds for appeal and how appellate courts review each issue. How long does a criminal appeal usually take, and what factors may cause delays? The possible outcomes of an appeal, including affirmance, reversal, modification, or remand. The mistakes that can derail an appeal and how to avoid them. Why hiring an experienced appellate attorney matters and how Brownstone Law helps clients fight for fair results in appellate courts.

Facing a conviction can be one of life’s most challenging moments, but it does not mark the end of your legal options. The U.S. justice system grants defendants the right to appeal a criminal conviction and request an appellate court to review their case for legal errors that may have influenced the verdict or sentence.

In FY 2024, the U.S. appellate courts reviewed 10,067 criminal appeals, and that number grew by 7%, reaching 10,092 cases by March 31, 2025, according to a report published by the Administrative Office of the U.S. Courts.

As more defendants turn to appeals to fix trial errors or unfair rulings, the process itself has become increasingly complex. Without knowing what to do and how to do it, even a single missed step or deadline can jeopardize your case. 

This guide explains how the criminal appeal process works and how to take the right legal steps toward a fair outcome.

Did You Know About The Origin of Criminal Appeals in the United States?  Until 1879, federal courts had no general right of appeal in criminal cases. Congress first allowed limited appeals that year. And by 1889, defendants in capital cases could even appeal directly to the U.S. Supreme Court, marking the birth of America’s modern appellate system.

Note: Any defendant convicted in a state or federal criminal court may file an appeal. Take note that it’s not a new trial, so no new evidence or witnesses are introduced.

Quick Overview: How a Criminal Appeal Works?

A criminal appeal is a request for an appellate court to review a conviction or sentence due to legal or procedural mistakes. It does not involve retrying the facts of the case. The process starts when the defendant files a Notice of Appeal by a specific deadline. Both sides then submit written briefs that present their arguments, which the appellate judges examine closely.

What Are Valid Grounds for an Appeal in Criminal Cases?

A criminal appeal must be based on specific legal grounds rather than dissatisfaction with the verdict. The appellate court only reviews whether mistakes occurred that affected the fairness or outcome of the trial. 

Common grounds include:

• Legal or Procedural Errors:

Mistakes in how the law was applied or how the trial was conducted, such as improper jury instructions or the wrongful admission or exclusion of evidence.

• Ineffective Assistance of Counsel:

When a defense attorney’s performance was so poor that it violated the defendant’s constitutional right to effective representation.

• Jury Misconduct:

Improper behavior by jurors that compromises fairness, such as considering evidence not presented in court, discussing the case before deliberations, or allowing bias to influence the verdict.

• Sentencing Errors:

Mistakes made during sentences, including penalties that fall outside statutory limits, reliance on incorrect legal standards, or misapplication of sentencing guidelines.

• Constitutional Violations:

Breaches of fundamental rights protected by the U.S. Constitution. For example, unlawful searches and seizures, forced confessions, or violations of due process and fair trial guarantees.

Standards of Review in Criminal Appeals 

Each of these grounds gives the appellate court a legal reason to review the case. But not every issue is examined with the same level of scrutiny. 

Depending on the type of error alleged, judges apply different standards of review to determine how closely to reexamine the trial proceedings.

How Does the Criminal Appeal Process Work?

The criminal appeal process follows a structured series of steps, each governed by strict rules and deadlines. 

• File the Notice of Appeal

The appeal process begins when the defendant (or their attorney) files a Notice of Appeal in the trial court. This must be done within strict deadlines, typically:  

• Federal cases: 14 days 
• State cases: 30–60 days 

• Assemble the Trial Record

Your appellate attorney obtains the official trial record, including transcripts, evidence, and court filings. This record serves as the foundation for the appeal, as the court will only review the evidence presented during the trial.

• Submit the Appellant’s Brief

The defense (now called the appellant) files a detailed written argument explaining why the conviction or sentence should be overturned. This brief identifies the legal errors that occurred and supports them with citations to case law and the record.

• Respondent’s Brief

The prosecution (the respondent) submits its own written brief defending the trial court’s decision and arguing why the conviction should stand. 

• Oral Argument 

In some cases, the appellate court may schedule an oral argument, where attorneys for both sides present their cases and answer the judges’ questions directly.

• Appellate Decision

After reviewing the written briefs and record (and oral arguments, if held), the panel of appellate judges issues a written opinion. The decision may include affirming, reversing, modifying, or remanding the case.