Donald J Trump’s first presidency (2017–2021) stands as one of the most contentious periods in modern US history marked by both institutional strain and a wide array of serious allegations.This book explores the broader national and geopolitical context of the presidency before focusing closely on the specific allegations made against Trump and his associates. Drawing heavily on court decisions, and the findings of special prosecutors and congressional committees, it examines how the US Constitution and criminal law responded to the actions of the 45th president. It explores prosecutions arising from Robert Mueller’s investigation, highlighting the role of international relations, and assesses allegations against Trump himself, including fraud, tax evasion, money laundering, obstruction of justice, sexual offences, and conduct linked to the 2016 and 2020 elections.The book offers clear analysis of pivotal constitutional mechanisms, including Trump’s use of the presidential pardon and Congress’s deployment of impeachment—twice during his tenure. It follows the major criminal cases pending against him by early 2024, including the implications of the Supreme Court’s ruling on presidential immunity.Written with clarity and authority for a non-American reader, the book distils the complex legal processes at work, illuminating the broader consequences for the US Constitution, criminal justice, and the rule of law.