Biological Weapons Convention


The Biological Weapons Convention, or Biological and Toxin Weapons Convention, is a disarmament treaty that effectively bans biological and toxin weapons by prohibiting their development, production, acquisition, transfer, stockpiling and use. The treaty's full name is the Convention on the Prohibition of the Development, Production and Stockpiling of Bacteriological and Toxin Weapons and on their Destruction.
Having entered into force on 26 March 1975, the BWC was the first multilateral disarmament treaty to ban the production of an entire category of weapons of mass destruction. The convention is of unlimited duration. As of May 2025, 189 states have become party to the treaty. Four additional states have signed but not ratified the treaty, and another four states have neither signed nor acceded to the treaty.
The BWC is considered to have established a strong global norm against biological weapons. This norm is reflected in the treaty's preamble, which states that the use of biological weapons would be "repugnant to the conscience of mankind". It is also demonstrated by the fact that not a single state today declares to possess or seek biological weapons, or asserts that their use in war is legitimate. In light of the rapid advances in biotechnology, biodefense expert Daniel Gerstein has described the BWC as "the most important arms control treaty of the twenty-first century". However, the convention's effectiveness has been limited due to insufficient institutional support and the absence of any formal verification regime to monitor compliance. The treaty has seen notable violations in offensive biological weapons programs of the Soviet Union, and of Ba'athist Iraq. Its Article VI mechanism for complaint of a violation has been invoked once, by Russia in 2022, regarding the debunked Ukraine bioweapons conspiracy theory.

History

While the history of biological warfare goes back more than six centuries to the Siege of Caffa in 1346 CE, international restrictions on biological warfare began only with the 1925 Geneva Protocol, which prohibits the use but not the possession or development of chemical and biological weapons. Upon ratification of the Geneva Protocol, several countries made reservations regarding its applicability and use in retaliation. Due to these reservations, it was in practice a "no-first-use" agreement only. In particular, it did not prevent multiple states from starting and scaling offensive biological weapons programs, including the United States and the Soviet Union.
The American biowarfare system was terminated in 1969 by President Nixon when he issued his Statement on Chemical and Biological Defense Policies and Programs. The statement ended, unconditionally, all U.S. offensive biological weapons programs. When Nixon ended the program the budget was $300 million annually.
The BWC sought to supplement the Geneva Protocol and was negotiated in the Conference of the Committee on Disarmament in Geneva from 1969 to 1972, following the conclusion of the negotiation of the Treaty on the Non-Proliferation of Nuclear Weapons. Of significance was a 1968 British proposal to separate consideration of chemical and biological weapons and to first negotiate a convention on biological weapons. The negotiations gained further momentum when the United States decided to unilaterally end its offensive biological weapons program in 1969 and support the British proposal. In March 1971, the Soviet Union and its allies reversed their earlier opposition to the separation of chemical and biological weapons and tabled their own draft convention. The final negotiation stage was reached when the United States and the Soviet Union submitted identical but separate drafts of the BWC text on 5 August 1971. The BWC was opened for signature on 10 April 1972 with ceremonies in London, Moscow, and Washington, D.C., and it entered into force on 26 March 1975 after the ratification by 22 states, including its three depositary governments.
There have been some concerned scientists who have called for the modernization of the BWC at the periodic Review Conferences. For example, Filippa Lentzos and Gregory Koblentz pointed out in 2016 that "crucial contemporary debates about new developments" for the BWC Review Conferences included "gain-of-function experiments, potential pandemic pathogens, CRISPR and other genome editing technologies, gene drives, and synthetic biology".

Treaty obligations

With only 15 articles, the BWC is relatively short. Over time, the treaty has been interpreted and supplemented by additional politically binding agreements and understandings reached by its States Parties at eight subsequent Review Conferences.

Summary of key articles

  • Article I: Never under any circumstances to develop, produce, stockpile, acquire, or retain biological weapons.
  • Article II: To destroy or divert to peaceful purposes biological weapons and associated resources prior to joining.
  • Article III: Not to transfer, or in any way assist, encourage, or induce anyone else to acquire or retain biological weapons.
  • Article IV: To take any national measures necessary to implement the provisions of the BWC domestically.
  • Article V: Undertaking to consult bilaterally and multilaterally and cooperate in solving any problems which may arise in relation to the objective, or in the application, of the BWC.
  • Article VI: Right to request the United Nations Security Council to investigate alleged breaches of the BWC and undertaking to cooperate in carrying out any investigation initiated by the Security Council.
  • Article VII: To assist States which have been exposed to danger as a result of a violation of the BWC.
  • Article X: Undertaking to facilitate, and have the right to participate in, the fullest possible exchange of equipment, materials and information for peaceful purposes.
The remaining articles concern the BWC's compatibility with the 1925 Geneva Protocol, negotiations to prohibit chemical weapons, amendments, Review Conferences, duration, withdrawal, joining the convention, depositary governments, and conditions for entry into force, and languages.

Article I: Prohibition of biological weapons

Article I is the core of the BWC and requires each state "never in any circumstances to develop, produce, stockpile or otherwise acquire or retain:
  1. microbial or other biological agents, or toxins whatever their origin or method of production, of types and in quantities that have no justification for prophylactic, protective or other peaceful purposes;
  2. weapons, equipment or means of delivery designed to use such agents or toxins for hostile purposes or in armed conflict."
Article I does not prohibit any specific biological agents or toxins as such but rather certain purposes for which they may be employed. This prohibition is known as the general-purpose criterion and is also used in Article II, 1 of the 1993 Chemical Weapons Convention. The general-purpose criterion covers all hostile uses of biological agents, including those developed in the future, and recognizes that biological agents and toxins are inherently dual use. While these agents may be employed for nefarious ends, they also have several legitimate peaceful purposes, including developing medicines and vaccines to counter natural or deliberate disease outbreaks. Against this background, Article I only considers illegitimate those types and quantities of biological agents or toxins and their means of delivery which cannot be justified by prophylactic, protective, or other peaceful purposes; regardless of whether the agents in question affect humans, animals, or plants. A disadvantage of this intent-based approach is a blurring of the line between defensive and offensive biological weapons research.
While it was initially unclear during the early negotiations of the BWC whether viruses would be regulated by it since they lie "at the edge of life"—they possess some but not all of the characteristics of life—viruses were defined as biological agents in 1969 and thus fall within the BWC's scope.
While Article I does not explicitly prohibit the "use" of biological weapons as it was already considered to be prohibited by the 1925 Geneva Protocol, it is still regarded as a violation of the BWC, as reaffirmed by the final document of the Fourth Review Conference in 1996.

Article III: Prohibition of transfer and assistance

Article III bans the transfer, encouragement, assistance, or inducement of anyone, whether governments or non-state actors, in developing or acquiring any of the agents, toxins, weapons, equipment, or means of delivery specified in Article I. The article's objective is to prevent the proliferation of biological weapons by limiting the availability of materials and technology which may be used for hostile purposes.

Article IV: National implementation

Article IV obliges BWC States Parties to implement the convention's provisions domestically. This is essential to allow national authorities to investigate, prosecute, and punish any activities prohibited by the BWC; to prevent access to biological agents for harmful purposes; and to detect and respond to the potential use of biological weapons. National implementing measures may take various forms, such as legislation, regulations, codes of conduct, and others. Which implementing measures are adequate for a state depends on several factors, including its legal system, its size and geography, the development of its biotechnology industry, and its participation in regional economic cooperation. Since no one set of measures fits all states, the implementation of specific obligations is left to States Parties' discretion, based on their assessment of what will best enable them to ensure compliance with the BWC.
A database of over 1,500 laws and regulations that States Parties have enacted to implement the BWC domestically is maintained by the non-governmental organization VERTIC. A similar database on national implementation measures developed by VERTIC and the United Nations Institute for Disarmament Research was launched in 2023. These concern the penal code, enforcement measures, import and export controls, biosafety and biosecurity measures, as well as domestic and international cooperation and assistance. For instance, the 1989 Biological Weapons Anti-Terrorism Act implemented the Convention for the United States. A 2023 VERTIC report concluded that "gaps persist in States Parties' legal frameworks for implementing the Convention at the national level". The BWC's Implementation Support Unit issued a background information document on "strengthening national implementation" in 2018 and an update in 2019.