Personal Profile

Katy is a litigator in Mishcon's Private department, specialising in commercial litigation predominantly for individuals and their businesses and families. Katy regularly advises clients on complex, high-stakes international litigation, deploying creative legal strategies to achieve her clients' specific objectives. 

In particular, Katy advises clients in relation to judicial review claims, fraud, commercial litigation and arbitration, reputation management (including defamation and harassment) and human rights.  Katy's breadth of experience ensures that she is well-placed to devise creative solutions to meet the needs of private clients in their wider personal and business lives.

Katy acted for Gina Miller in her successful judicial review claim against the Government, arguing that Article 50 could not be triggered without the express authorisation of Parliament.  Katy also made legal precedent by securing the first "fake news" injunction.

In 2014 Katy was seconded to the civil liberties organisation, Liberty, assisting the policy and legal teams in responding to draft legislation, writing policy papers and advising in respect of a wide range of human rights issues.  She previously worked for David Lammy MP, for the US Congressman Robert Wexler and was seconded to Obama for America as a campaigner in the swing state of North Carolina during the 2008 presidential election.

Key Experience

Judicial Review

  • Acting for Gina Miller in the High Court claim and Supreme Court appeal against the Government, successfully arguing that it was unconstitutional for the Government to trigger Article 50 without an authorising Act of Parliament. The case was of legal and political significance, and is widely considered to be the most important constitutional law case in over 150 years. 
  • Advising a Brazilian religious group in a judicial review claim against the Home Office's decision to deny a licence to import and consume a drink used in their religious ceremonies, engaging arguments relating to drug safety and freedom to practice religion.

International arbitration and commercial litigation

  • Acting for BSGR in a multi-billion dollar ICSID arbitration against the Government of Guinea, based on the illegal expropriation of mining rights by the government.  The complex claim involves allegations of corruption and bribery and an understanding of the legal framework relating to disputes against state entities.
  • Acting for a company to remove the Chairman of an arbitral tribunal based on an appearance of bias.
  • Advising a client in relation to a shareholder dispute, engaging company law and immigration issues.
  • Successfully negotiating a settlement for several defendants in a £80million conspiracy to defraud claim, involving allegations of fraud and negligence.

Reputation management, harassment and confidentiality

  • Setting legal precedent by securing the first "fake news" injunction against Persons Unknown, curbing an online fake news campaign against a British businessman.
  • Acting for the owners of a family antiques business to successfully obtain an injunction preventing the disclosure of confidential information
  • Advising a private individual in relation to harassment and blackmail attempt by a former girlfriend.
  • Advising a tourist attraction in Spain in relation to a public smear campaign disseminating false allegations relating to its animal welfare record.

Articles and Publications

  • "Article 50 litigation—putting a spotlight on the UK’s constitution", James Libson and Katy Colton, 8 November 2016, LexisNexis Public Law Analysis
  • "Gina Miller’s Brexit victory is a triumph of democracy over politics", Emily Nicholson and Katy Colton, 4 November 2016, Guardian
  • "Businessman’s fake news troll halted by injunction in legal first", Francis Gibb, 10 July 2017, The Times
  • "Injunction halts ‘fake news’ campaign against UK businessman", Ben Quinn, 10 July 2017, Guardian

Career History

Managing Associate, Mishcon de Reya LLP
Associate, Mishcon de Reya LLP
Solicitor, Mishcon de Reya
Trainee Solicitor, Mishcon de Reya
Secondee to Barack Obama's campaign team, North Carolina - Obama for America
Researcher for David Lammy MP, House of Commons
Legislative intern for Robert Wexler, United States House of Representatives


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