How much does it cost to hire Mark for a appellate case?

Cost depends on the type of matter, the fee model (contingency, flat, hourly), and how contested the case becomes. Mark walks through the likely range during the consult so there are no surprises.

Does Mark offer a free consultation?

Mark charges for the initial consult; that fee is credited toward representation if you retain Mark's office. Some appellate attorneys offer free consults — check Mark's current terms during booking.

How long do appellate cases in Florida typically take?

Simple appellate matters can wrap in a few weeks; disputed cases can run 6–18 months from intake to resolution, longer if the matter goes to trial. Mark gives a realistic estimate for your facts at the consult — vague answers here are a red flag.

Can Mark take my case if I'm outside Tampa?

Mark is licensed in Florida. Matters governed by Florida law are the natural fit. Out-of-state matters are handled case-by-case, sometimes with local co-counsel. Ask during intake — Mark will tell you if the case is a fit or refer you to someone closer to your court.

What should I bring to my first meeting with Mark?

Bring every document that touches the dispute: contracts, correspondence, police or medical reports, filed pleadings, invoices, photographs, insurance letters. Also bring a written timeline of what happened, in your own words. Mark will filter what matters — over-preparing at intake is always cheaper than needing a second meeting.

Is Mark accepting new appellate clients right now?

Mark's intake status shifts week to week. Submit the form; the office will confirm availability or refer the matter out.

Mark J. O'Brien, Appellate Attorney in Tampa

Quick answer

Mark J. O'Brien is a founder based in Tampa, FL. The practice focuses on Appellate, Consumer, and Criminal Defense. Mark has over 28 years of legal experience. Currently practicing at O'Brien Hatfield, PA. Rated 5.0 out of 5 from 3 client reviews.

Based in: Tampa, FL
Experience: over 28 years
Known for: Appellate · Consumer · Criminal Defense

Handles Appellate, Consumer, and Criminal Defense matters from Tampa, FL.
Over 28 years of practice as a licensed attorney.

Areas of practice

Mark's practice areas in Tampa

Mark concentrates on appellate, consumer, criminal defense, drug crimes, and environmental. Each area below outlines the kind of case Mark handles, typical outcomes to expect, and how the intake process starts.

Appellate cases in Tampa, Florida

Mark takes appellate matters in Tampa, Florida. Typical engagements include intake calls to scope the issue, review of any records or filings you already have, and a written strategy memo before Mark agrees to represent you.

Consumer cases in Tampa, Florida

Mark takes consumer matters in Tampa, Florida. Typical engagements include intake calls to scope the issue, review of any records or filings you already have, and a written strategy memo before Mark agrees to represent you.

Criminal Defense cases in Tampa, Florida

Mark takes criminal defense matters in Tampa, Florida. Typical engagements include intake calls to scope the issue, review of any records or filings you already have, and a written strategy memo before Mark agrees to represent you.

Drug Crimes cases in Tampa, Florida

Mark takes drug crimes matters in Tampa, Florida. Typical engagements include intake calls to scope the issue, review of any records or filings you already have, and a written strategy memo before Mark agrees to represent you.

Environmental cases in Tampa, Florida

Mark takes environmental matters in Tampa, Florida. Typical engagements include intake calls to scope the issue, review of any records or filings you already have, and a written strategy memo before Mark agrees to represent you.

Biography

Mark J. O'Brien, appellate attorney serving Tampa

Mark J. O'Brien is a founder based in Tampa, FL. The practice focuses on Appellate, Consumer, and Criminal Defense. Mark has over 28 years of legal experience. Currently practicing at O'Brien Hatfield, PA. Rated 5.0 out of 5 from 3 client reviews. Mark works from Tampa, Florida and takes on appellate matters across the region.

Attorney Mark J. O’Brien is a nationally recognized federal criminal defense attorney with nearly thirty years of experience in criminal courts all throughout the country. After beginning his professional career as a Miami, Florida prosecutor in the late 1990’s, Mr. O’Brien organized his own law firm in 2002 based upon the professional lessons he learned to that point in his life with the goal defending those accused of federal and state crimes with a mix of old school values and new school ideas. He is the firm’s managing partner.

During his first decade in private practice from 2002 to 2012, Mr. O’Brien defended individuals and corporations charged with federal crimes throughout federal criminal courts in Florida. From 2012 to the present, Mr. O’Brien has accepted the defense of clients charged in federal criminal courts throughout the entire country, in addition to his previously established federal criminal defense practice in all federal courts in Florida. Case after case, success after success, in federal court after federal court, all throughout the country, has resulted in a growing legacy. To put it simply, Mr. O’Brien wins and, as a result, he is a lawyer in demand.

Mr. O’Brien is a licensed member of the Bar of the State of Florida (1998), the Bar of the Commonwealth of Massachusetts (1998), and the Bar of the State of Montana (2023). He has practiced federal criminal defense as a member or a pro hac vice member of the following federal appellate and district courts:

• Supreme Court of the United States of America

• United States Court of Appeals for the First Circuit

• United States Court of Appeals for the Second Circuit

• United States Court of Appeals for the Ninth Circuit

• United States Court of Appeals for the Eleventh Circuit

• United States District Court for the Northern District of Alabama

• United States District Court for Alaska

• United States District Court for the Eastern District of Arkansas

• United States District Court for the Central District of California

• United States District Court for the Southern District of California

• United States District Court for Connecticut

• United States District Court for the Southern District of Florida

• United States District Court for the Middle District of Florida

• United States District Court for the Northern District of Florida

• United States District Court for the Southern District of Georgia

• United States District Court for the Middle District of Georgia

• United States District Court for the Northern District of Georgia

• United States District Court for the Southern District of Illinois

• United States District Court for the Southern District of Indiana

• United States District Court for Kansas

• United States District Court for the Eastern District of Kentucky

• United States District Court for Massachusetts

• United States District Court for the Eastern District of Michigan

• United States District Court for the Western District of Michigan

• United States District Court for the Northern District of Mississippi

• United States District Court for the Southern District of Mississippi

• United States District Court for the Western District of Missouri

• United States District Court for Montana

• United States District Court for the Southern District of New York

• United States District Court for the Northern District of New York

• United States District Court for the Western District of New York

• United States District Court for North Dakota

• United States District Court for Northern District of Oklahoma

• United States District Court for Rhode Island

• United States District Court for the Middle District of Tennessee

• United States District Court for the Eastern District of Texas

• United States District Court for the Western District of Texas

• United States District Court for the Northern District of Texas

• United States District Court for the Eastern District of Virginia

• United States District Court for the Eastern District of Washington

• United States District Court for the Western District of Washington

• United States District Court for the Southern District of West Virginia

Mr. O’Brien handles all federal criminal areas of practice, including but not limited to: Tax Fraud, Mail Fraud, Wire Fraud, Bank Fraud, Mortgage Fraud, Securities Fraud, Medicare Fraud, Health Care Fraud, Bribery, IRS Issues, Embezzlement, Insider Trading, Ponzi Schemes, Money Laundering, Sarbanes Oxley, Conspiracy to Commit a Federal White-Collar Crime, and all other Federal White Collar Crimes. Mr. O’Brien also handles Child Pornography Possession Offenses, Child Pornography Production Offenses, Child Pornography Transportation Offenses, Child Pornography Distribution Offenses, Child Pornography Receipt Offenses, Sex Trafficking Offenses, Conspiracy to Commit a Federal Sex Crime, and all other Federal Sex Crime Offenses. Mr. O’Brien also represents those charged with Drug Crimes, Gun Crimes, Conspiracy to Commit Drug and Gun Crimes, and all other General Federal Criminal Defense matters. He also handles Federal Grand Jury Investigations and Pre-File Criminal Investigations, including but not limited to Targets of a Federal Grand Jury Investigation, Subjects of a Federal Grand Jury Investigation, Witnesses of a Federal Grand Jury Investigation, and SEC, FBI, HSI, DEA, ATF, CIA, and NSI Investigations. The bottom line is if you are charged or being investigated for a federal crime, Mr. O’Brien will defend you.

Mr. O’Brien realized early on in his career that the people best positioned to defend a federal defendant are those individuals who once investigated and prosecuted federal defendants. It is important to stay one step ahead of the prosecution and their investigators and what better way to accomplish this goal than by hiring people who once did it?

Mr. O’Brien’s federal criminal defense team includes a former United States Marine Intelligence Officer and a retired United States Drug Enforcement Administration (DEA) federal special agent. This team member has participated in all aspects of narco-trafficking law enforcement, including surveillance operations, wiretap operations, and arrest operations at the state and federal level. While a federal agent, he managed macro and micro narco-trafficking, money laundering, and weapons investigations at the state, national, and worldwide level. Over his career, he participated in world deployments, wherein he advised foreign nationals on the investigation of narco-traffickers, money launderers, and weapons distributors. He finished his career in the State of Florida, wherein he retired after twenty-five years with the DEA as a Group Supervisor. He understands how federal, state, and local law enforcement agencies and prosecutors operate nationwide.

Mr. O’Brien’s federal criminal defense team also includes a retired Internal Revenue Service, Criminal Investigations Division, (IRS CID) federal special agent, who is also a certified fraud examiner and a forensic accountant. This team member provides invaluable knowledge and expertise in all the firm’s white-collar fraud and money laundering cases. While he was with the IRS CID, he was a special agent, group manager, assistant chief and executive officer in New York City, Denver, and Philadelphia. While a special agent, he investigated and prosecuted drug cartels and organized crime members such as the New York, New England, and Philadelphia Mafia, Frank Lucas (later played by Denzel Washington in the movie about his life American Gangster), and Nicki Barnes.

Mr. O’Brien’s federal criminal defense team also includes a former Senior Supervisory United States Federal Probation Officer who served the federal judges for over twenty-five years. He has a wide-ranging background related to the United States Sentencing Guidelines and criminal statutory penalties. Over the course of his career, he prepared and analyzed nearly a thousand presentence investigation reports for accuracy and completeness (including those prepared by subordinate probation officers). As a member of the law firm, and no other, he uses the knowledge and expertise he gained during his federal government career to assist firm clients in the pre-plea, pre-sentencing, and post-sentencing phases of their federal criminal cases.

Mr. O’Brien grew up and attended college in New York, attended law school near Philadelphia, and started his career as a prosecutor in Miami. As a result, there is almost nothing Mr. O’Brien has not seen, done, or dealt with in or out of a criminal courtroom over the course of his career. New York raised, Philly tough, and Miami tested, Mr. O’Brien brings nearly thirty years of criminal court experience to those accused of crimes in federal criminal courts throughout Florida, Massachusetts, and now the entire nation. Mr. O’Brien has the resources, both in his team and in his experience and his training, to tackle your federal criminal case and accomplish the only objective that matters: Win.

Thus, if you are being investigated and/or prosecuted by federal agents and/or federal prosecutors and are need of a federal criminal defense attorney – and a federal criminal defense team – anywhere in the United States of America, all Mr. O’Brien needs is a Wi-Fi Password and a plane to defend you.

Mark's approach to appellate cases

Attorney Mark J. O’Brien is a nationally recognized federal criminal defense attorney with nearly thirty years of experience in criminal courts all throughout the country. After beginning his professional career as a Miami, Florida prosecutor in the late 1990’s, Mr. O’Brien organized his own law firm in 2002 based upon the professional lessons he learned to that point in his life with the goal…

Clients Mark works with

Mark reviews new inquiries case-by-case for appellate, consumer, and criminal defense matters in Tampa and the surrounding Florida area.

Credentials

Credentials — where Mark studied and practices

Siena College
B.A. Widener · 1995

Jurisdictions

Mark's state bar admissions

Montana United State
2023 · ACTIVE
Massachusetts U.S. D
1998 · ACTIVE
Florida
1998 · ACTIVE

Mark studied at B.A. Widener in Siena College.

Law school and academic background

Mark completed B.A. Widener in Siena College. Formal legal training is one signal of substantive knowledge — the day-to-day practice Mark runs in Florida is where that training gets applied to real client questions.

Locations

Mark J. O'Brien's office in Tampa

Mark's primary office is at 511 W Bay St.Suite 330, Tampa, FL, 33606. In-person meetings are by appointment; a phone intake usually comes first.

Main office

O'Brien Hatfield, PA

511 W Bay St.Suite 330

Tampa, FL 33606

Open in Google Maps

Client feedback

Client reviews of Mark J. O'Brien — 5.0/5 rating from 3 verified client reviews

Every review below is from a verified client of Mark. Reviews cover communication, case outcome, and value — the three signals that matter most when comparing appellate attorneys in Tampa.

5.0

3 client reviews

Client ratings are sourced from public records and editorial research. Reviews on LawyersListed are accepted from verified clients once Mark J. O'Brien claims this profile.

Read all reviews

Hiring guide

How to hire Mark J. O'Brien — what to expect in your first consultation

Working with a new appellate attorney should feel structured. Here's how the first two conversations with Mark usually go, from the moment you request a consult to the day representation begins.

Consultation formats and pricing

Mark charges for the initial consult. That fee is credited toward representation if you retain Mark's office.

What to bring to your first meeting

Bring any documents you already have — police reports, medical records, filed pleadings, correspondence from an insurer, a copy of the contract at issue. If you're not sure, err on the side of bringing everything; Mark will tell you what matters and what doesn't.

Questions to ask a appellate attorney in Tampa, Florida

A short list to run through before you commit: How many appellate matters have you handled in the last year? What's your fee structure? Who else in the office will work on this? What's your realistic estimate of timeline and range of outcomes? How do I reach you between meetings?

Fees & payment

Fees, payment methods, and consultation options for Mark

Mark discusses fees during intake so the arrangement fits the matter. Contingency, hourly, and flat-fee options are all common in appellate practice — ask which fits.

Hourly rates, contingency fees, and flat-fee options

Every appellate matter is priced differently. Simple document review might be a flat fee. Injury litigation is often contingency. Complex commercial disputes usually run hourly with a retainer. Mark confirms the model in the engagement letter before any work starts.

Payment methods and payment plans

Mark's office accepts standard payment methods. Ask about payment plans if the retainer is a stretch — many appellate practices work with clients on structured schedules.

Frequently asked

Frequently asked questions about Mark J. O'Brien

How much does it cost to hire Mark for a appellate case?
Cost depends on the type of matter, the fee model (contingency, flat, hourly), and how contested the case becomes. Mark walks through the likely range during the consult so there are no surprises.
Does Mark offer a free consultation?
Mark charges for the initial consult; that fee is credited toward representation if you retain Mark's office. Some appellate attorneys offer free consults — check Mark's current terms during booking.
How long do appellate cases in Florida typically take?
Simple appellate matters can wrap in a few weeks; disputed cases can run 6–18 months from intake to resolution, longer if the matter goes to trial. Mark gives a realistic estimate for your facts at the consult — vague answers here are a red flag.
Can Mark take my case if I'm outside Tampa?
Mark is licensed in Florida. Matters governed by Florida law are the natural fit. Out-of-state matters are handled case-by-case, sometimes with local co-counsel. Ask during intake — Mark will tell you if the case is a fit or refer you to someone closer to your court.
What should I bring to my first meeting with Mark?
Bring every document that touches the dispute: contracts, correspondence, police or medical reports, filed pleadings, invoices, photographs, insurance letters. Also bring a written timeline of what happened, in your own words. Mark will filter what matters — over-preparing at intake is always cheaper than needing a second meeting.
Is Mark accepting new appellate clients right now?
Mark's intake status shifts week to week. Submit the form; the office will confirm availability or refer the matter out.

Community Q&A

Real questions asked by Florida residents in the last few months, answered by appellate attorneys like Mark J. O'Brien. Each link opens the full answer thread.

How do I appeal a workers' compensation decision in Florida?
After my workers' comp claim was denied in Miami, I want to fight it because my injury is legitimate. I’ve consulted with my doctor and have documentation to prove it. I’m looking
1 verified answer · Appellate · Florida
How do I file an appeal against a payday loan judgment in Louisiana?
I lost a court case regarding a payday loan in Baton Rouge and want to know how to file an appeal. The lender used questionable practices that I want to contest. What specific step
1 verified answer · Appellate · Louisiana
What rights do I have in appealing a credit report dispute in Alaska?
I disputed an error on my credit report in Anchorage, but it was rejected. This error is affecting my ability to secure a loan, and I want to know what rights I have in appealing t
1 verified answer · Appellate · Alaska
What is the procedure for appealing a zoning decision in Michigan?
I’m fighting a zoning decision made by our local council in Detroit that restricts my property development. I want to know the exact steps for appealing this decision in Michigan.
1 verified answer · Appellate · Michigan
What is the cost to appeal a traffic ticket in New Jersey?
I received a traffic ticket in Newark for a speeding violation, but I wasn’t speeding. I’m considering appealing the ticket, but I’m worried about the costs involved. Can someone e
1 verified answer · Appellate · New Jersey
Can a federal court case be appealed in Illinois state court?
I was involved in a federal lawsuit in Chicago, but I lost my case concerning a contract dispute. I’m confused about the appeal process; can I appeal in state court or do I have to
1 verified answer · Appellate · Illinois

Areas served

Appellate attorneys serving Tampa, Miami and Orlando in Florida

Mark handles appellate matters throughout Florida. Each city below is a direct link into the search page for verified appellate attorneys in that community.

Mark J. O'Brien, Appellate Attorney in Tampa, Florida

Quick answer