Houston Federal Criminal Defense Lawyer
A federal case can begin long before an arrest. It may start with agents at the door, a search warrant, a grand-jury subpoena, a target letter, or an investigation that has been building quietly for months. Sam R. Cammack III represents clients facing serious federal criminal matters and is admitted to practice in the U.S. District Courts for the Southern and Eastern Districts of Texas.
Contacted by federal agents? Do not guess about whether you are a witness, subject, or target. Learn what to do first, review Sam Cammack's background, or see selected criminal case results.
Sam R. Cammack III is admitted to practice in the U.S. District Courts for the Southern and Eastern Districts of Texas. Federal admission is different from claiming a particular result or specialization in every federal offense. Prior results do not guarantee future outcomes.
Draft for legal review by Sam R. Cammack III · Texas Bar No. 24014415 · Updated September 9, 2026
Short answer: what makes a criminal case federal?
A criminal case is federal when the United States has authority to prosecute the alleged conduct under federal criminal law. The case may involve a federal statute, interstate or international conduct, federal property or programs, federally regulated activity, or another federal connection required by the offense.
Federal investigations are commonly conducted by agencies such as the FBI, DEA, ATF, Homeland Security Investigations, IRS Criminal Investigation, the U.S. Postal Inspection Service, and other federal agencies. Federal prosecutions are handled by Assistant U.S. Attorneys in the appropriate United States District Court.
Some conduct can potentially violate both Texas law and federal law. That does not make the cases identical. The charging statutes, prosecutors, investigative agencies, court rules, detention process, discovery, plea negotiations, sentencing framework, and consequences can differ substantially.
Federal investigations often begin before charges are filed
If federal agents have contacted you, the most important question may be what role the government believes you have in the investigation, and that may not be obvious from the conversation.
Do not assume “they only want to ask a few questions” means you are not at risk
You may have the right to decline a voluntary interview and to speak with counsel before answering questions. Do not lie to federal investigators, destroy records, delete messages, alter documents, or instruct anyone else to conceal evidence. Preserve what may be relevant and get advice before deciding how to respond.
Agents contact you
A lawyer can help determine whether contact is voluntary, what agency is involved, and whether counsel should communicate with investigators before any interview.
Subpoena for testimony or records
A federal grand-jury subpoena can require testimony, documents, or records. Deadlines matter, and a witness generally cannot have counsel inside the grand-jury room.
You are told you are a target
A target letter can state that prosecutors believe substantial evidence links a person to a federal offense. It should be reviewed before any response or appearance.
Home, business, phone, or data searched
A search warrant can reveal that an investigation is already advanced. Preserve the warrant and property inventory and avoid obstructing the search.
Money or property is seized
Federal criminal investigations can include asset-seizure or forfeiture issues that may move on a separate procedural track from the criminal charge.
Charges have already been filed
Once a complaint or indictment is filed, initial appearance, detention or release, arraignment, discovery, motions, plea negotiations, and trial preparation begin quickly.
Types of federal charges and investigations
Federal criminal jurisdiction covers many statutes. The categories below are common examples. They are not a claim that every federal offense is accepted by the firm. Sam should confirm the final scope of representation before publication.
Federal Drug Trafficking & Conspiracy
DEA, HSI, FBI, and multi-agency investigations involving distribution, conspiracy, interstate activity, or large quantities of controlled substances.
Federal Firearms Offenses
ATF and other federal investigations involving prohibited possession, firearms connected to other offenses, trafficking, or related federal allegations.
Wire, Mail & Bank Fraud
Fraud allegations involving interstate communications, financial institutions, business transactions, electronic payments, or federal programs.
Healthcare & Government-Program Fraud
Investigations involving Medicare, Medicaid, healthcare billing, federal benefits, grants, procurement, or other government-funded programs.
Money Laundering
Federal allegations involving financial transactions, proceeds of specified unlawful activity, concealment, structuring, or movement of funds.
Tax & IRS Criminal Investigations
IRS-CI matters involving alleged tax crimes, financial records, false returns, evasion, or related financial conduct.
Identity Theft & Cybercrime
Federal investigations involving identity information, computer access, electronic fraud, account compromise, or interstate digital conduct.
Federal Robbery & Violent Crime
Certain robberies, firearms-related violent crimes, carjacking, kidnapping, and other offenses can fall within federal jurisdiction when statutory requirements are met.
Conspiracy & Multi-Defendant Cases
Federal conspiracy charges can focus on an alleged agreement and a broader course of conduct involving multiple people, agencies, warrants, and extensive discovery.
Related state-law allegations may also be relevant. See the firm's pages for Drug Possession & Narcotics, Robbery & Theft, and Murder & Assault.
Federal criminal case vs. Texas state criminal case
| Issue | Texas State Case | Federal Criminal Case |
|---|---|---|
| Law alleged | Texas criminal law | Federal criminal law enacted by Congress |
| Prosecutor | District / county attorney or other state prosecutor | U.S. Attorney's Office / Assistant U.S. Attorney |
| Investigators | Local police, sheriff, DPS and other state/local agencies | FBI, DEA, ATF, HSI, IRS-CI and other federal agencies, often with state/local partners |
| Trial court | Texas county or district court | United States District Court |
| Felony charging | Texas grand-jury procedures | Federal felony indictment by grand jury unless indictment is lawfully waived |
| Sentencing | Texas punishment statutes and sentencing rules | Federal statutes, statutory minimums/maximums where applicable, advisory U.S. Sentencing Guidelines, and federal sentencing law |
| Post-release system | Texas parole may apply depending on offense/sentence | Modern federal sentences generally use supervised release rather than traditional federal parole |
The same underlying conduct can sometimes produce both state and federal exposure. Whether both sovereigns investigate or prosecute depends on the statutes, facts, agencies, prosecutorial decisions, and constitutional limits.
Typical stages of a federal criminal case
Not every case follows the exact same order. Some begin with an investigation or subpoena; others begin with an arrest, criminal complaint, or sealed indictment.
- InvestigationFederal agents collect evidence through interviews, records, surveillance, subpoenas, search warrants, cooperating witnesses, digital evidence, and other investigative methods.
- Charging / Grand JuryFor federal felonies, prosecutors generally present the matter to a grand jury unless indictment is waived. The indictment gives formal notice of the federal charges.
- Initial Appearance & Detention / ReleaseA magistrate judge advises the defendant of rights and charges and addresses whether the person will remain detained or be released subject to conditions.
- Arraignment & DiscoveryThe defendant enters a plea, and the defense begins reviewing the government's evidence, reports, recordings, data, warrants, witness material, and other discovery.
- Pretrial MotionsDepending on the case, counsel may litigate suppression, search-warrant issues, statements, discovery, severance, dismissal, evidentiary questions, or other pretrial matters.
- Plea Negotiations or TrialFederal cases can resolve through a negotiated plea or proceed to trial. The decision depends on the evidence, charges, exposure, defenses, guideline issues, and the client's objectives.
- SentencingIf there is a conviction or guilty plea, the court considers the governing statute, presentence report, advisory Sentencing Guidelines, arguments from both sides, and federal sentencing factors.
- Appeal / Post-Judgment IssuesDepending on the case and any appeal waiver, appellate or post-conviction issues may follow judgment.
Why federal sentencing requires its own strategy
Federal sentencing is not simply the Texas punishment range moved into a different courthouse.
Statutory minimums & maximums
Congress sets punishment ranges for federal offenses, and some statutes carry mandatory minimum sentences or enhanced penalties based on specified facts.
U.S. Sentencing Guidelines
The Guidelines are advisory, but guideline calculations can heavily influence sentencing analysis. Offense characteristics, criminal history, adjustments, and other rules can materially change the range.
Presentence investigation
A probation officer typically prepares a presentence report addressing the offense, criminal history, personal background, guideline calculation, and other sentencing information.
Federal sentencing rules change. The U.S. Sentencing Commission publishes the current Guidelines Manual, primers, and amendments. A guideline estimate should be based on the actual indictment, evidence, criminal history, and applicable manual, not a generic online calculator.
Southern & Eastern Districts of Texas
Admitted to practice before both U.S. District Courts
Sam R. Cammack III is admitted to practice in the U.S. District Court for the Southern District of Texas and the U.S. District Court for the Eastern District of Texas.
The Southern District includes the Houston Division and is one of the busiest federal districts in the country. The Eastern District includes federal courts serving areas such as Beaumont, Lufkin, Tyler, Texarkana, Plano, and Sherman.
Official court resources: Southern District of Texas · Eastern District of Texas
Southern District of Texas
The U.S. Attorney's Office for the Southern District of Texas handles federal prosecutions across 43 counties and operates divisions including Houston, Galveston, Victoria, Corpus Christi, Brownsville, McAllen, and Laredo.
Eastern District of Texas
The Eastern District's criminal prosecutors handle federal matters including narcotics, firearms, fraud, violent crime, white-collar cases, public corruption, cyber-related matters, and other federal offenses.
Federal court admission plus serious-felony trial experience
Until Sam verifies federal case-specific results for publication, this page keeps federal admission and broader criminal-trial experience separate rather than implying that an unrelated state result was a federal case.
Former felony prosecutor
Sam previously served as a felony prosecutor in Harrison County, Texas and has been licensed in Texas since 2002. That background is relevant to criminal investigation, charging decisions, evidentiary disputes, negotiation, and trial preparation.
Serious-felony trial practice
Sam's broader criminal-defense practice includes homicide and other serious-felony jury-trial experience. See selected case results and his attorney biography.
Houston federal criminal defense frequently asked questions
What makes a criminal case federal instead of state in Texas?
A case is federal when the United States has authority to prosecute the alleged conduct under federal law. That can arise from a specific federal statute, interstate or international conduct, federal property or programs, federally regulated activity, or another federal connection required by the offense. Some conduct can violate both state and federal law, so the same incident may create exposure in more than one system.
What should I do if FBI, DEA, ATF, HSI, or IRS agents contact me?
Be polite, do not obstruct, and do not lie, but do not assume you must participate in a voluntary interview immediately. Ask for the agents' names and contact information, preserve any paperwork they give you, and speak with federal criminal defense counsel before deciding whether and how to answer questions. If agents have a warrant, do not interfere with its execution.
What is a federal target letter?
A target letter generally tells a person that prosecutors consider them a target of a federal grand-jury investigation. DOJ materials describe a target as someone to whom prosecutors or the grand jury believe substantial evidence links the person to the commission of a crime. The letter should be reviewed before contacting prosecutors, appearing before the grand jury, or providing documents beyond what is legally required.
What should I do if I receive a federal grand-jury subpoena?
Do not ignore it, destroy records, or improvise a response. A subpoena may require testimony, documents, or both. Federal grand-jury proceedings are secret, and a witness's attorney generally cannot sit inside the grand-jury room during testimony. Counsel can still advise the witness before the appearance, communicate with prosecutors, evaluate privilege and Fifth Amendment issues, and address the scope and timing of document production.
Can I be under federal investigation before I am arrested or indicted?
Yes. Federal investigations can last weeks, months, or longer before charges become public. Agents may use subpoenas, warrants, interviews, cooperating witnesses, surveillance, financial records, digital evidence, and other investigative tools before prosecutors decide whether to seek an indictment.
Can the same conduct be charged in both Texas state court and federal court?
Potentially, yes. State and federal governments are separate sovereigns, and some conduct violates both state and federal statutes. Whether both systems actually prosecute depends on the facts, statutes, investigative agencies, prosecutorial policies, prior proceedings, and constitutional law.
What is a federal conspiracy charge?
A federal conspiracy charge generally alleges an agreement between two or more people to commit a federal offense. The precise elements depend on the conspiracy statute. In multi-defendant cases, prosecutors may use communications, financial records, surveillance, cooperating witnesses, controlled transactions, or other evidence to argue that participants knowingly joined the alleged agreement.
What happens after a federal indictment?
The case moves into formal federal-court proceedings. Depending on whether the person is already in custody, the next stages can include arrest or summons, initial appearance, detention or release proceedings, arraignment, discovery, motions, plea negotiations, and trial preparation. A federal indictment is an accusation, not proof of guilt.
How is federal sentencing different from Texas sentencing?
Federal sentencing uses federal statutes and an advisory Sentencing Guidelines system rather than Texas punishment law. The court considers statutory minimums and maximums where applicable, the guideline calculation, criminal history, a presentence report, arguments from both sides, and the federal sentencing factors. Guideline analysis can become one of the most technical parts of a federal case.
Can federal criminal charges be dismissed?
Yes, but dismissal depends on a legal or factual basis and is never automatic. Federal defense issues can include whether the indictment states an offense, jurisdiction, search and seizure, statements, discovery violations, evidentiary problems, witness credibility, proof of the required federal nexus, or prosecutorial decisions. Some cases also change substantially through superseding indictments or plea negotiations.
Is there parole in a modern federal criminal sentence?
Traditional federal parole generally does not apply to modern federal offenses. Federal sentences commonly include a term of supervised release after imprisonment. Sentence-reduction credits, compassionate release, good-time rules, and other Bureau of Prisons or statutory mechanisms are separate from traditional parole and should not be treated as a guaranteed release date.
How much does a federal criminal defense lawyer cost in Houston?
Federal fees vary significantly based on whether the matter is pre-indictment or already charged, the number of defendants and counts, discovery volume, digital or financial evidence, detention litigation, experts, motions, sentencing issues, and whether the case is expected to go to trial. The firm should quote the specific matter after reviewing the investigation or indictment and explain what the fee includes. The initial consultation with this firm is free. Call 713-224-4444.
Related criminal-defense pages and legal resources
All Practice Areas
See the firm's complete criminal-defense and legal-services hub.
Drug Possession & Narcotics
State drug charges and trafficking allegations that may overlap with DEA, HSI, or federal conspiracy investigations.
Robbery & Theft Defense
State property and robbery charges that may overlap with federal bank robbery, fraud, firearms, or interstate allegations.
Murder & Assault Defense
Serious violent-felony defense where federal firearms, conspiracy, organized-crime, or other federal allegations may also arise.
Case Results
Selected documented criminal-defense verdicts, dismissals, no-bills, mistrials, and other outcomes.
About Sam R. Cammack III
Former felony prosecutor, Texas criminal-defense trial lawyer, and federal-court-admitted attorney.
The Firm & Legal Team
Learn how the office handles communication, preparation, and criminal-defense matters.
Articles & Legal Insights
Plain-English explanations of Texas and federal criminal-law issues.
Free Case Review
Contact the office about a federal investigation, subpoena, warrant, indictment, or pending criminal case.
Official federal criminal-process resources
U.S. Department of Justice: Federal Criminal Process
U.S. Sentencing Commission: Guidelines
Official Texas federal courts
U.S. District Court: Southern District of Texas
U.S. District Court: Eastern District of Texas
If the federal government is already investigating, the case may be further along than it looks
Bring or send the target letter, subpoena, warrant, indictment, complaint, agent contact information, or any other paperwork you received. Early review can help identify the agency, court, allegations, immediate deadlines, and whether communication with investigators should go through counsel.
Sam R. Cammack III · 1001 West Loop South, Suite 700, Houston, TX 77027
This page provides general educational information and is not legal advice. Federal criminal statutes, investigative procedures, detention rules, Sentencing Guidelines, mandatory minimums, forfeiture rules, court admissions, and local procedures contain exceptions and can change over time. The exact statute, district, indictment, offense date, criminal history, agency, evidence, plea agreement, and other facts can change the analysis. An indictment or criminal complaint is an accusation, not proof of guilt. Prior results do not guarantee or predict the outcome of another case.