International law for political scientists 

Terminology matters a great deal to lawyers. Political scientists study international law, but we don't necessarily have the legal background to understand the significance of the terms. Below is my interpretation of a few terms that often come up in the literature and are covered in my Database of Human Rights. I've drawn chiefly from the Vienna Convention on the Law of Treaties and the UN Treaty Collection, and then translated into political science-ese. Warning: I am not a lawyer! My summaries below (like any summary) are simplifications. If they are incorrect, please contact me. Thanks.

• Creation: the act of writing down a treaty and (often, for human rights agreements) passing it through some body such as the UN General Assembly, ILO, etc.
  

• Signature: the act of approving of a treaty's text. This often occurs on the same date as a treaty's 'creation,' but not always. Signature alone does not create a legal obligation to comply with the terms of the agreement. However, signatories do take on an obligation not to work against the principles in the treaty. This is probably why the George W. Bush administration went to the trouble of 'unsigning' the Rome Statute.* The database does not differentiate acceptance, approval, accession, or succession from ratification because they all carry the same international legal effect. Instead, the ratification variable is a catch-all indicating whether a state accepts a treaty as legally binding.

• Ratification: the process by which a country consents to be bound by a treaty. The terms consent and bound are crucial here. Indeed, for international legal scholars, one of the main reasons that treaties are to be obeyed (pacta sunt servanda) is that states join them by their own accord. The idea that international law has a binding character once a country ratifies is equally important, although political scientists (and some international lawyers) are quick to point out that a country may have acknowledged a treaty as binding and still completely fail to comply.

• Entry into force: treaties often stipulate that a certain number (or percentage) of states must ratify a treaty before it enters into force. Before that happens, the treaty is not technically legally binding, even on states that have ratified. Human rights treaties usually have very low entry into force provisions, or none at all.

• (Acceptance/approval)*: these have the same legal effect as ratification. Acceptance/ approval sometimes take place in states where constitutional law does not require the head of state to consent.

• (Accession)*: occurs when a state consents to be bound by a treaty, when other states have already negotiated and signed it. It has the same legal effect as ratification. 

• (Succession)*: occurs when a state takes on the international legal obligations of a previous state (typically because of dissolution, unification, etc.).

* The database does not differentiate acceptance, approval, accession, or succession from ratification because they all carry the same international legal effect. Instead, the ratification variable is a catch-all indicating whether a state accepts a treaty as legally binding.

(Left-handers can sign treaties, too)