UN Security Council Veto Power

The United Nations Security Council "veto power" refers to the power of the permanent members of the United Nations Security Council to veto any "substantive" resolution. A permanent member's abstention or absence does not prevent a draft resolution from being adopted. However, the veto power does not apply to "procedural" votes, as determined by the permanent members themselves. A permanent member can also block the selection of a Secretary-General, although a formal veto is unnecessary since the vote is taken behind closed doors.

The unconditional veto possessed by the five governments has been seen by critics as the most undemocratic character of the UN. Critics also claim that veto power is the main cause for international inaction on war crimes and crimes against humanity. However, the United States refused to join the United Nations in 1945 unless it was given a veto. The absence of the United States from the League of Nations contributed to its ineffectiveness. Supporters of the veto power regard it as a promoter of international stability, a check against military interventions, and a critical safeguard against U.S. domination.

Article 27 of the United Nations Charter states:

Although the "power of veto" is not explicitly mentioned in the UN Charter, the fact that "substantive" decisions by the UNSC require "the concurring votes of the permanent members", means that any of those permanent members can prevent the adoption, by the Council, of any draft resolutions on "substantive" matters. For this reason, the "power of veto" is also referred to as the principle of "great power unanimity" and the veto itself is sometimes referred to as the "great power veto".

The idea of states having a veto over the actions of international organizations was not new in 1945. From the foundation of the League of Nations in 1920, each member of the League Council, whether permanent or non-permanent, had a veto on any non-procedural issue. From 1920 there were 4 permanent and 4 non-permanent members, but by 1936 the number of non-permanent members had increased to 11. Thus there were in effect 15 vetoes. This was one of several defects of the League that made action on many issues impossible.

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