The "British Islands" are defined as the United Kingdom (of Great Britain and Northern Ireland) together with the Channel Islands and the Isle of Man - see the Interpretation Act 1978. Great Britain comprises England and Wales together with Scotland. The Channel Islands and the Isle of Man are referred to as "Crown Dependencies" and they are not part of the United Kingdom and are part of the European Union only to a limited extent. All of this is the result of lengthy historical development. The various governmental and legal arrangements are, to say the least, complex.
report was published in March 2010. The Ministry of Justice in London facilitates communication between the Crown Dependencies and the British government - see here.
United Kingdom Parliament
Scottish Parliament ................ Welsh Assembly ...................... Northern Ireland Assembly
Tynwald - Isle of Man Parliament - the oldest Parliament in the World
The Jersey legislature is the States Assembly. The Guernsey legislature (which legally covers Alderney and Sark as the Bailiwick of Guernsey) is the States of Deliberation. Alderney is in many respects self-governing (apart from some issues such as policing, taxes, and social security) and has its own legislature. Sark also has its own legislature - Chief Pleas.