Wikipedia: The West Lothian question

The West Lothian question was a question posed by Tam Dalyell, MP for the Scottish constituency of West Lothian during a debate over Scottish devolution in the 1970s. The name was coined in 1977 by Enoch Powell.

The question is twofold:

• How can it be right that MPs elected to Westminster from Scottish constituencies have no ability to affect the issues of their constituents which have been devolved to the Scottish Parliament, and
  
• If power over Scottish affairs is devolved to a Scottish Parliament, how can it be right that MPs representing Scottish constituencies in the Parliament of the United Kingdom will have the power to vote on issues affecting England (including those that don't affect Scotland), but English MPs will not have the power to vote on Scottish issues?
  

With the passing of the Scotland Act in 1998, and the creation of the Scottish Parliament in 1999, this anomaly[1] has come into existence.