The Global Legal Research Center at the Law Library of Congress recently released a report describing the legal frameworks that the United Nations, European Union, and 73 countries have adopted or are considering adopting for dealing with foreign terrorist fighters. The report, completed in late 2014 and updated this month, points out variations between countries that already have provisions for dealing with foreign fighters on the books, and details proposals that some countries have introduced in response to a September 2014 U.N. Security Council resolution on the matter.
Here's the report's introductory summary:
This report contains information on provisions in place or being considered by the United Nations, the European Union, and seventy-three countries on the treatment of individuals who join and fight for terrorist organizations in foreign countries. A number of countries are considering action now following the September 2014 adoption of a United Nations Security Council resolution expressing concern about the threat of foreign terrorist fighters. Many nations, as illustrated below, already have punishments applicable to such fighters, including imprisonment and/or loss of citizenship. In a number of jurisdictions, penalties for joining terrorist organizations increase when the individual recruits others or undergoes military training with those organizations. A unique approach is being taken in one city in Denmark, where instead of facing punishment, returning fighters are being given study or employment opportunities. In addition to the report on these jurisdictions, two maps have been included to illustrate the findings.