Dr Williams' research focuses on the sometimes difficult relationships between judges and politicians - where the rule of law meets the power of politics. He has sought to explain the increasing intervention by judges into sensitive public policy domains, such as immigration, anti-discrimination and homelessness.
- British politics from 1900 to the present day, including elections, parties, referendums etc
- US politics from 1787 to the present day, including elections and political parties
- The role of the courts in politics
Dr Williams appears regularly on local BBC radio.