Can Greece Be Expelled from the Eurozone? Toward a Default Rule on Expulsion from International Organizations

The ongoing European crisis has raised uncomfortable questions about the conditions under which treaty-based unions of nations like the EU or the EMU can legally expel a member — Greece being the most obvious candidate. The EU, for example, has rules governing the voluntary withdrawal of members, but says nothing about whether a member can be expelled. As a matter of international law, what does the silence mean? Put differently: What is the default rule regarding expulsions when a treaty says nothing about forced withdrawals? Is there an absolute bar on expulsion, as some have suggested? Conversely, is there an implicit right to expel? Or can material breaches of a treaty justify expulsion? And if fault is not required, must the expelled member state be compensated in some way?