Legal Aspects of the CTBT

John Burroughs
Western States Legal Foundation
rev. November 25, 1997

Current status: The Comprehensive Test Ban Treaty (CTBT) was adopted in September 1996 by the United Nations General Assembly and has now been signed by about 150 countries.  Under a generally accepted rule of international law, set forth in article 18 of the Vienna Convention on the Law of Treaties, signatories to a treaty are bound to refrain from acts which would defeat the object and purpose of a treaty.  The U.S. Arms Control and Disarmament Agency has stated that this rule bars CTBT signatories from carrying out nuclear test explosions.  President Clinton has also stated that the adoption of the CTBT established a "global norm" against such explosions.  In addition, the U.S. is prohibited by federal statute from carrying out nuclear test explosions unless another country tests. 

The CTBT regime will be fully established when the treaty "enters into force".  This requires ratification (in addition to signature) of the treaty by the 44 states in the world which have commercial or research nuclear reactors (a recognition that nuclear power is the foundation for a nuclear weapons program).  Of those states, India and Pakistan, both undeclared nuclear weapon states, as well as North Korea, have not signed the treaty. Reflecting the concerns of many countries, India objects to the nuclear weapon states' (NWS) laboratory testing programs as an evasion of the CTBT, and has declared its intention not to sign or ratify the treaty absent an unequivocal commitment by the NWS to a process of global nuclear disarmament.  Pakistan has stated that it will not endorse the CTBT unless India does so. 

Article XIV of the CTBT provides that a conference of states that have ratified may be held at the request of a majority of those states three years or later after the treaty was opened for signature, i.e. in September 1999 or later.  This conference would "decide by consensus what measures consistent with international law may be undertaken to accelerate the ratification process in order to facilitate the early entry into force of this Treaty".  Additional such conferences could be held on an annual basis. 

Paths to establishing the CTBT regime: The CTBT Organization Preparatory Commission is now creating the treaty's elaborate verification system.  According to the Commission's executive secretary, Wolfgang Hoffman, it will be operational in two to three years whether or not the treaty has entered into force.
In September, he was in Washington seeking $20 million in funding for the system owed by the US.
Though it is less than one-half of one percent of the $4.5 billion annual budget for the Stockpile Stewardship and Management Program, Congress so far has refused to meet this obligation.  Other possible steps towards establishment of the CTBT regime include the following: 

1) The NWS could make a joint declaration at the Conference on Disarmament in Geneva or a Nuclear Non-Proliferation Treaty (NPT) review proceeding (the next one is in April 1998) that they will respect the prohibition on nuclear test explosions pending the CTBT's entry into force, thus reinforcing their existing obligation as signatories to abide by the treaty's terms. 

2) The NWS could agree to the commencement of multilateral negotiations on global nuclear disarmament in the Conference on Disarmament and curtail or eliminate their laboratory testing programs, thus substantially meeting India's objections. 

3) The NWS could ratify the CTBT and then seek to persuade/coerce India to endorse the treaty. This appears to be present US strategy. 

4) The NWS and other states could agree to provisional application of the CTBT to consenting states pending its entry into force, as authorized by Article 25 of the Vienna Convention.  Such a step could be taken at a conference on facilitation of early entry into force held in the fall of 1999 or later or by some other means.  This procedure has been employed with other multilateral treaties.  Notably, the General Agreement on Trade and Tariffs (GATT) was made binding for decades by the Protocol of Provisional Application.  The US became a party to the Protocol and GATT simply by signing the Protocol, without Senate approval.  However, the Senate would likely strongly resist formal US adherence to the CTBT absent its approval, and also only ratifying states can participate in CTBT conferences on early entry into force. 

Scope of the prohibition: Article I of the CTBT prohibits "any nuclear weapon test explosion or any other nuclear explosion" (emphasis added).  The preamble "recogniz[es]" that the prohibition will "constrain[] the qualitative improvement of nuclear weapons and end[] the development of advanced new types of nuclear weapons".  Exactly what "nuclear explosions" are prohibited will be determined by parties to the CTBT, and possibly the International Court of Justice, on the basis of the treaty text, the (sparse) negotiating record, and the future practice of all states parties, including their statements at review conferences.  A strict construction of the prohibition as banning all kinds of experimental nuclear explosions would advance the treaty's disarmament objectives, help attract India's adherence to the treaty, and promote the long-term viability of the non-proliferation regime. 

The NWS have stated that the treaty bars explosions involving a self-sustaining chain reaction. Accordingly, they claim, "subcritical" tests are permitted though they involve the production of neutrons by fissile materials. However, such tests involve a nuclear "explosion" though a chain reaction does not occur.  For example, it remains to be determined whether the CTBT bars tests of possible "fourth-generation" weapons in which fissile material is "burned", without a chain reaction, at a rapid rate resulting in yields of tens or 100s of tons. 

Another area of concern is devices that would cause "pure fusion" explosions that destroy the initiating device.  Research into such devices, for example using chemical explosive driven pulsed power, is underway, including in joint US-Russian experiments.  Especially since such devices could have large yields and are potentially compact enough to be "weaponizable", there is already expert opinion that CTBT parties should determine their testing to be banned. 

Still another area of concern is large laser facilities like the US National Ignition Facility and the French Megajoule Laser that are designed to produce, on a repeated basis in containment vessels, sizable fusion explosions (on the order of 100 pounds of yield, enough to partially destroy a building).  The NWS, as well as such advanced non-nuclear weapon states as Germany, contend that such explosions are not banned by the CTBT.  They cite the CTBT negotiating record, as well as an asserted understanding under the NPT that such explosions conducted for civilian purposes by non-nuclear weapon states are permissible.  However, the CTBT on its face bars any "nuclear explosion", whether "civilian" or military.  Further, such experiments conducted by NWS in support of nuclear weapons maintenance and development seem to violate both the letter and the intent of the CTBT.  Thus whether the prohibition applies in this area also remains open to determination by all CTBT parties.