Legal Aspects of the CTBT
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
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
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.