Tiana Demas

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About Tiana

Tiana is a veteran federal prosecutor and a top authority on cybersecurity, data privacy and national security issues surrounding the use of novel technologies. Drawing on her broad experience in the tech industry and more than 10 years at the US Attorney’s Office for the Eastern District of New York (EDNY), Tiana represents clients in complex privacy and data breach litigation in federal courts across the US. She also represents clients in government investigations (criminal and civil), and she helps companies strategically respond to data breaches, cyberattacks, privacy issues and regulatory enforcement actions.

At EDNY, Tiana prosecuted many high-profile national security and cybercrime cases, including the first-ever trial conviction of an ISIS terrorist. Having served in the civil and criminal divisions at EDNY, she tried nearly a dozen cases to verdict and successfully argued numerous cases before the US Court of Appeals for the Second Circuit. Tiana held multiple leadership roles at EDNY, including deputy chief of general crimes, where she trained and supervised new prosecutors on the fundamentals of criminal prosecution, and computer hacking and intellectual property coordinator (CHIP), where she led EDNY’s global cybercrime practice, supervised cybercrime investigations, and led private-sector outreach and training on cybersecurity and emerging threats.

As a line prosecutor, Tiana led investigations and prosecutions involving economic and trade sanctions, the Espionage Act, the Foreign Agents Registration Act (FARA), securities and financial fraud, the Foreign Corrupt Practices Act (FCPA), international money laundering, the Racketeer Influenced and Corrupt Organizations (RICO) Act, and violent crimes.

Tiana’s notable representations at Cooley include:

Privacy and security class actions

  • Securing the 12(b)(6) dismissal of a putative class action lawsuit filed against Marsh McLennan arising out of a cyberattack – the case is currently on appeal to the Second Circuit
  • Representing Dotdash Meredith in class action lawsuits brought under the Video Privacy Protection Act (VPPA) in the US District Court for the Southern District of New York and the US District Court for the District of Massachusetts
  • Representing AARP in class action lawsuit brought under the VPPA in the US District Court for the Northern District of California
  • Representing the National Association of Realtors in a privacy class action alleging violations of Michigan’s Preservation of Personal Privacy Act in the US District Court for the Eastern District of Michigan
  • Representing Meredith in multiple consolidated class actions in the US District Court for the Northern District of Illinois and the US District Court for the Southern District of Iowa that allege the company violated state right of publicity laws
  • Representing Metromile in a data breach class action filed in the US District Court for the Northern District of California
  • Securing a default judgment for Google in affirmative litigation against a Cameroon-based defendant who abused Google’s services to commit a puppy fraud scheme
  • Representing a technology company in the Northern District of California in John Doe litigation against anonymous defendants who hacked into the company’s Wi-Fi network and disrupted its operations
  • Representing Prodege in John Doe litigation against an anonymous individual who engaged in online harassment of Prodege employees

Government investigations

  • Representing a videoconferencing service provider in a Federal Trade Commission (FTC) investigation concerning the company’s privacy and security practices
  • Representing a mobile advertising company in an FTC investigation concerning the alleged nonpayment of virtual currency rewards, resulting in a favorable consent order
  • Representing an insurance technology company in a data breach investigation by the New York state attorney general’s office
  • Conducting an internal investigation for a computing company into potential theft of trade secrets by a former employee
  • Representing a public biotech company in a Department of Justice and Securities and Exchange Commission insider trading investigation

Pro bono

  • Representing a defendant in Louisiana post-conviction relief proceedings challenging the constitutionality of his non-unanimous jury conviction
  • Representing an Ecuadorian national seeking political asylum in an appeal to the US Court of Appeals for the Eighth Circuit

In her career at the DOJ, Tiana worked on and oversaw notable cases, including:

  • United States v. Willner, the prosecution of a US-based day trader who traded securities in tandem with overseas co-conspirators who hacked into accounts at major brokerage firms to artificially move stock prices
  • United States v. Kuyumcu, the export control conviction of a CEO who illegally exported tonnage quantities of metallic powder with nuclear applications to Iran
  • United States v. Pugh, the first-ever trial conviction of an ISIS terrorist on material support and obstruction of justice charges
  • United States v. Ametovski, the prosecution and conviction of a Macedonian national who operated Codeshop, a global cybercrime marketplace of stolen credit and debit card information
  • United States v. Bermudez Arciniegas et al. and United States v. Alvarez et al., the prosecution of 12 Columbian nationals and 26 US nationals for international money laundering involving a major Columbian drug cartel 
  • Multiple prosecutions involving leaders of the Sinaloa drug trafficking cartel, including United States v. Jesus Reynaldo Zambada Garcia (a key cooperating witness during the 2019 trial of Joaquín “El Chapo” Guzmán)

Before joining Cooley, Tiana was associate general counsel, cybersecurity law and investigations, at Meta, where she managed and led large interdisciplinary teams to investigate and respond to complex cyberattacks and threats directed at the company and its worldwide community of users. She also helped lead the company’s cybersecurity compliance program.

Tiana began her career as a litigation associate at Salans (now known as Dentons) before joining Hogan Lovells as a commercial litigator.

Publications and presentations

  • Co-author of “US Supreme Court Narrows Scope of Computer Fraud and Abuse Act in Van Buren,” Cooley cyber/data/privacy insights blog, June 9, 2021
  • Co-author of “Second Circuit Rules Individuals Have Standing to Sue for ‘Increased Risk’ of Identity Theft,” Cooley cyber/data/privacy insights blog, April 30, 2021
  • Co-author of “Illuminating SolarStorm: Implications for National Security Strategy and Policy,” The Aspen Institute (Aspen Digital), March 4, 2021
  • Role “Censorship in Cyberspace,” Columbia Law School, April 2019
  • Presenter for “Evolving Criminal Law in the High-Tech World,” New York City Bar Association event, April 30, 2019


Columbia Law School
JD, 2002

Columbia College, Columbia University
BA, 1999, magna cum laude

Court admissions

US Court of Appeals for the Second Circuit

US District Court for the Southern District of New York

US District Court for the Eastern District of New York

US District Court for the Eastern District of Michigan