Caleb Mason

[email protected]

T: (213) 406-2949
F: (213) 613-0550



Assistant United States Attorney, Southern District of California, 2007-2009; Associate Professor of Law, Southwestern Law School, 2009-2012; Associate, Miller Barondess LLP, 2012-2014.

Education and Honors

J.D., cum laude, Georgetown University, 2005; Editor-in-Chief, Georgetown Law Journal; Moot Court; Ph.D., Columbia University, 2001; BA, cum laude, Colby College, 1995. Commissioner, City of Claremont Police Commission.


Hon. D. Michael Fisher, United States Court of Appeals for the Third Circuit, 2005-06.

Bar Admissions

California, Illinois, United States Supreme Court, United States Court of Appeals for the Ninth Circuit, United States Court of Appeals for the Third Circuit, United States District Court for the Southern District of California, United States District Court for the Central District of California; United States District Court for the Northern District of Illinois.

A representative sampling of Mr. Mason’s experience is as follows:

Selected Publications:
  • Currently in the top 5% of authors in the Social Science Resource Network (SSRN), ranked by number of downloads.  Mr. Mason’s papers are available on SSRN at:
  • The Market For Mules: Risk and Compensation of Cross-Border Drug Smugglers, (with David Bjerk), 39 INTERNATIONAL REVIEW OF LAW AND ECONOMICS 58 (2014) (peer-reviewed)
  • Fractured Group Speech Acts and the Holding of NFIB v. Sebelius, THE AFFORDABLE CARE ACT DECISION, Routledge 2014 (Fritz Allhoff & Mark Hall, eds.) (peer-reviewed)
  • Inter-Judge Sentencing Disparity on the Federal Bench: An Examination of Drug Smuggling Cases in the Southern District of California, 25 FEDERAL SENTENCING REPORTER 190 (2013) (with David Bjerk) (peer-reviewed)
  • New Police Technologies, the Good-Faith Exception, and the Development of Fourth Amendment Law: Warrantless GPS Tracker Evidence After United States v. Jones, 13 NEVADA LAW JOURNAL 60 (2012)
  • The Confrontation Clause and the Border Patrol: Applying the “Primary Purpose” Test to Multifunction Agencies, 96 MARQUETTE LAW REVIEW 793 (2013) (with Jessica Berch)
  • Framing Context, Anonymous Internet Speech, and Intent: New Uncertainty About the Constitutional Test for True Threats, 41 Southwestern Law Review 43 (2011)
  • Blind Mules?: New Caselaw and New Data on the Border Smuggling Industry, Criminal Justice Vol. 26, No. 3, at 16 (Fall 2011)
  • Jay-Z’s “99 Problems,” Verse 2: A Close Reading With Fourth Amendment Guidance for Cops and Perps, 56 St. Louis University Law Review 567 (2011)
      • Reprinted in HIP-HOP AND THE LAW: THE KEY WRITINGS THAT FORMED THE MOVEMENT, forthcoming, Palsgrave-Macmillan, 2014 (DeAndre Cummings, ed.,)
    • Reprinted in Slate: Longform, Sep. 12, 2012
  • International Cooperation, Drug Mule Sentences, and Deterrence: Preliminary Thoughts from the Cross-Border Drug Mule Survey, 27 Southwestern Journal of International Law 189 (2011)
  • The Police-Prosecutor Relationship and the No-Contact Rule: Conflicting Incentives After Montejo v. Louisiana and Maryland v. Shatzer, 58 Cleveland State Law Review 747 (2010)
  • A Rational Post-Booker Proposal for Reform of Federal Sentencing Enhancements for Prior Convictions, 31 Northern Illinois Law Review 339 (2011) (with Scott Lesowitz)
  • The Use of Immigration Status in Cross-Examination of Witnesses: Scope, Limits, Objections, 33 American Journal of Trial Advocacy 549 (2010)
    • Reprinted in: 31 IMMIGRATION & NATIONALITY Law Review 923 (2010)
  • What is Truth? Setting the Bounds of Justiciability in Religiously-Inflected Fact Disputes, 26 Journal of Law and Religion 91 (2010) (Peer-reviewed)
  • An Aesthetic Defense of the Nonprecedential Opinion: The Easy Cases Debate in the Wake of the 2007 Amendments to the Federal Rules of Appellate Procedure, 55 UCLA Law Review 643 (2008).
  • Faith, Harm, and Neutrality: Some Complexities of Free Exercise Law, 44 Duquesne Law Review 225 (2006).
  • Doctrinal Considerations for Fast Food Obesity Suits, 40 Tort Trial and Insurance Practice Law Journal 75 (2004) (Peer-reviewed).
Selected Popular Writing:
  • “Don’t Pretend the Kavanaugh Facts Are Unknowable,” The Atlantic, Sep. 28, 2018
  • “On Criminal Justice, Kavanaugh Might Be More Centrist than Kennedy,” The Crime Report, July 24, 2018
  • “Can Steve Bannon Claim Executive Privilege?  Absolutely Not.” Op-Ed, Los Angeles Times, January 19, 2018
  • “Jeff Sessions Can’t Shut Up,” Op-Ed, Los Angeles Times, June 16, 2017
  • “Why Did South Carolina Punt on the Slager Case?” The Crime Report, May 8, 2017
  • “Will Gorsuch Be Another Scalia on Criminal Justice Issues? Not Likely,” The Crime Report, Feb. 1, 2017
  • Utah v. Strieff: No Consequences for an Admittedly Illegal Seizure,” The Crime Report, Aug. 8, 2016
  • “Why Is California Thumbing Its Nose At a Federal Court?” The Crime Report, March 17, 2016
    • Reprinted in Prison Legal News, May 5, 2016
  • “Gang Validation, Good Time Credit, and the Ex Post Facto Clause in the California Prison System,” The Crime Report, Jan. 14, 2016
  • “Challenging the Reliability of Drug-Dog Alerts After Florida v. Harris,” CaseText, Aug. 17, 2015
  • “Was the Ferguson Grand Jury Misled?,” The Crime Report, February 24, 2015
  • “What DAs Across the Country Can Learn from Ferguson,” The Crime Report, January 6, 2015
  • “Lender Liability to Guarantors: Doctrine, Pitfalls and Strategy,” Daily Journal, Nov. 24, 2014
  • “Crime and Religious Immunity: Congress Needs to Set Limits,” The Crime Report, Oct. 14, 2014
  • “Refusing to Testify Against Your Church,” The Crime Report, Oct. 14, 2014
  • “The Real Fourth Amendment Problem: Getting Substantive Issues Decided at All,” The Crime Report, July 9, 2014
  • “Cell Phone Ruling Is No Threat to Effective Policing,” The Crime Report, July 8, 2014
  • “The Myth of ‘Activist’ Judges,” The Crime Report, Dec. 10, 2013
  • “Drug Sniffing Dogs and 18th Century Justice,” The Crime Report, April 2, 2013
    • reprinted in Salon as “Justice Scalia, Civil Libertarian?”
  • “Plain View Computer Searches: General Petraeus’ Waterloo,” The Crime Report, Jan. 8, 2013
  • “Drug Traffickers: Is Prison Time a Deterrent?” The Crime Report, Dec. 11, 2012
Selected Media:
  • MSNBC News, Dec. 26, 2017 (on White House attacks on the FBI)
  • Law & Crime Network, Nov. 17, 2017 (on the Adam Matos murder trial)
  • MSNBC, “Hardball,” Aug. 11, 2017 (on the Russia investigation developments)
  • MSNBC News, Aug. 4, 2017 (on government leaks and DOJ subpoenas to journalists)
  • MSNBC News, July 15, 2017 (on the Russia investigation and Trump campaign meetings)
  • MSNBC News, June 10, 2017 (on the Russia investigation and Comey testimony)
  • MSNBC News, May 20, 2017 (on the Russia investigation)
  • Cheddar TV, January 12, 2017 (on conflicts of interest created by Trump family businesses)
  • Cheddar TV, Dec. 23, 2016 (on constitutional issues raised by Palantir and government data-mining)
  • CNN, Aug. 31, 2016 (on United States v. Wexler, internet threats case)
  • Multiple networks, Aug. 2016-present (Joseph A. Bank suit commercial)
  • MSNBC News and “Alex Witt Show,” July 2, 2016 (on the H. Clinton email investigation and the B. Clinton / L. Lynch meeting)
  • MSNBC, “Alex Witt Show,” June 18, 2016 (on the Orlando shooting investigation)
  • BBC News, Jan. 11, 2016 (on the Sean Penn-Chapo Guzman interview)
  • MSNBC News, Nov. 3, 2015 (on the Houston anti-discrimination ordinance)
  • MSNBC News, Sep. 9, 2015 (on the Kentucky gay-marriage standoff)
  • MSNBC News, Sep. 8, 2015 (on the Kentucky gay-marriage standoff)
  • MSNBC News, Sep. 3, 2015 (on the Tom Brady Deflate-Gate decision)
  • MSNBC, “The Cycle,” July 30, 2015 (on the U. of Cincinnati shooting)
  • MSNBC, “The Cycle,” July 20, 2015 (on the Bill Cosby deposition)
  • Associated Press, July 11, 2015 (on contraband watch in California prisons)
  • MSNBC, “The Cycle,” June 24, 2015 (on the Boston bombing case)
  • MSNBC, “The Cycle,” June 5, 2015 (on the Dennis Hastert investigation)
  • MSNBC, “The Cycle,” May 15, 2015 (on the Boston bombing case)
  • MSNBC, “The Cycle,” May 4, 2015 (on the Freddie Gray case in Baltimore)
  • San Diego Union-Tribune, May 2, 2015 (on border drug smuggling)
  • MSNBC, “The Cycle,” Apr. 13, 2015 (on the South Carolina police shooting)
  • MSNBC, “The Cycle,” Apr. 8, 2015 (on the Tsarnaev Boston bombing case)
  • MSNBC, “The Cycle,” Apr. 7, 2015 (on the Tsarnaev Boston bombing case)
  • MSNBC, “The Cycle,” Feb. 17, 2015 (on the Chris Kyle murder trial)
  • MSNBC, “The Last Word with Lawrence O’Donnell,” Dec. 4, 2014 (on the police-prosecutor relationship)
  • MSNBC, “The Cycle,” Dec. 4, 2014 (on Eric Garner case)
  • MSNBC, “The Cycle,” Dec. 3, 2014 (on Eric Garner case)
  • MSNBC, “The Cycle,” Nov. 25, 2014 (on Ferguson grand jury decision)
  • MSNBC, Nov. 24-25, 2014 (on Ferguson grand jury decision)
  • MSNBC, “The Cycle,” Nov. 21, 2014 (on grand jury deliberations)
  • MSNBC, “The Cycle,” Aug. 19, 2014 (on release of information from criminal investigations)
  • USA Today, June 16, 2014 (on GPS tracking and United States v. Jones)
  • The Guardian, June 2, 2014 (on “contraband watch” in U.S. prisons)
  • St. Louis University Law Journal online, April 30, 2014 (on the 10-year anniversary of “99 Problems”)
  • NBC News, May 30, 2013 (on cross-border drug trafficking)
  • SFGate, February 6, 2013 (on the Chappell v. Mandeville case)
  • Christian Science Monitor, April 4, 2012 (on the George Zimmerman case)
  • Christian Science Monitor, March 29, 2011 (on the Barry Bonds case)
  • Riverfront Times, July 30, 2012; KPCC, Madeleine Brand Show, July 13, 2012; Huffington Post, July 10, 2012; Gawker, July 11, 2012; Above the Law, July 11, 2012 (and many others) (on my article on Jay Z’s “99 Problems”)
Representative Cases:
  • Obtained reversal of conviction, dismissal of all charges, and immediate release of defendant, based on challenge to identification of client, in appeal of federal drug-trafficking case in which client was serving 15-year sentence.
  • Obtained $2.2 million jury verdict in wrongful arrest/abuse of police authority suit, in case charging that sheriff’s deputy fabricated criminal allegations against client in retaliation for client making complaint about deputy’s conduct.
  • Represents restaurant owner alleging Brown Act confict-of-interest violations by municipal government.
  • Obtained reduction in lifetime supervised release term, Government return of the defendant’s fine, and permission to travel, in case involving challenging sentence imposed for nonviolent sex offense
  • Obtained exonerations and judicial findings of factual innocence in two high-profile cases alleging sexual assault.
  • Obtained dismissal of case against clients in lawsuit alleging multimillion-dollar embezzlement of corporate funds.
  • Obtained dismissal of felony threat charges in high-profile case after uncovering evidence of misidentification of client.
  • Won a significant first-impression appeal in the Ninth Circuit, United States v. Campbell, protecting the rights of federal prisoners on supervised release.
  • Obtained multi-million dollar settlement for fire department union in First Amendment retaliation lawsuit.
  • Successfully defended multiple firefighters in internal disciplinary investigations.
  • Represents multiple victims in high-profile torture and abuse case.
  • Obtained settlement (confidential amount) for the family of an arrestee who committed suicide in a city jail.
  • Obtained probation sentences with no jail time in multiple vehicular homicide cases.
  • Represents multiple firefighters and firefighter unions in disputes with municipalities.
  • Represents families suing property developer in multi-million dollar fraud case.
  • Successfully defended a high-profile federal criminal case involving alleged internet threats against the FBI.
  • Obtained judgment for client against large corporation that sought to avoid enforcement through putative name change of corporate subsidiary.
  • Successfully resolved multiple cases concerning allegations of misconduct involving high-profile individuals in entertainment and professional sports..
  • Successfully represented firefighters and their union in major First Amendment case against municipality.
  • Obtained probation sentence with no jail time in felony DUI case charging great bodily injury.
  • Represents a luxury homebuilder in a major federal asset forfeiture case.
  • Obtained dismissal of all charges in a kidnapping/sexual assault case with a potential life sentence.
  • Obtained judicial finding of factual innocence for criminal defendant in contested hearing, and won order sealing and expunging arrest and charging records over government opposition.
  • Successfully defended a major bank in a multi-million dollar fraud trial.
  • Petitioned for Certiorari in the U.S. Supreme Court in significant Fourth Amendment and actual-innocence cases.
  • Represented business clients in intellectual property disputes, including video game designers and jewelry designers.
  • Obtained dismissal of fraud claims against small business owner.
  • Successfully resolved dispute between small business owners over dissolution of their company.
  • Represents small independent musicians in negotiations and disputes with production companies.
  • Supervised numerous investigations, including gun trafficking, drug trafficking, counterfeiting, and environmental crimes.
  • Represented victims of alleged assaults by LAPD officers.
  • Litigated over 40 cases in the Ninth Circuit Court of Appeals, including employment, criminal, immigration, and Eighth Amendment cases. Appellate victories include:
    • obtaining a favorable settlement for a female construction worker subjected to sexual harassment on her worksite;
    • winning an appeal on behalf of a prisoner who was denied dental care;
    • winning an appeal to prevent the deportation of an immigrant mother with two U.S.-citizen children;
    • winning an appeal to prevent the deportation of a Chinese immigrant who feared persecution in China because of his Mormon faith.
  • Regularly consults on application of empirical research in drug smuggling cases.
  • Represented numerous federal and state criminal defendants from investigation through appeal.