Some filing cabinets make more noise locked than open. In Geneva, the most revealing paperwork in the biological weapons world is not a smoking gun, a leaked lab memo, or a suitcase of samples. It is a yearly ritual of forms—quiet, administrative, almost forgettable—submitted under the Biological Weapons Convention to calm suspicion in a treaty with no real inspection corps. But there is a catch hidden in the fine print. Those reports can be made public. They can also be kept inside the diplomatic club. In a system built to reduce doubt, secrecy was never supposed to be the headline. And yet, here we are.

The Case For

A transparency system with a built-in curtain

The official record leaves no mystery about the architecture. The United Nations Office for Disarmament Affairs says the BWC’s Confidence-Building Measures, or CBMs, were introduced after the 1986 Second Review Conference to “prevent or reduce the occurrence of ambiguities, doubts and suspicions” and to improve cooperation in peaceful biological activity. States Parties are supposed to submit annual reports by 15 April covering the previous calendar year, with information on research centers, biodefense programs, unusual outbreaks, legislation, past programs, and vaccine production facilities. Just as important, UNODA states plainly that governments may choose to make those submissions either publicly available or restricted to other States Parties only.

That one option changes the emotional temperature of the whole system. On paper, the BWC’s only formal transparency tool is real. In practice, parts of that tool can remain invisible to journalists, watchdogs, researchers, and the public whose safety the treaty is supposed to reinforce. The public UN CBM portal says only reports that governments consent to disclose can be clicked through by non-registered users. Everyone else sees the shell of a transparency mechanism, not always its contents.

Why critics think restriction blunts the treaty’s only flashlight

That tension has not gone unnoticed. A 2025 Politics and the Life Sciences study by Matthew P. Shearer and colleagues argued that restricted access to many submissions has limited the practical value of CBMs, alongside low participation, concerns about completeness, and weak analytic capacity. The researchers also noted a striking possibility: some governments may not even realize their submissions remain restricted because the choice can persist by habit rather than deliberate policy. If true, that is not a thriller plot. It is stranger. A transparency regime can become half-sealed by default.

The institutional weakness underneath all this is already familiar to readers who followed our deep dive on who actually reviews BWC CBM reports. The BWC has no standing verification body like the OPCW. The Implementation Support Unit receives and distributes CBMs, but official briefings have emphasized that CBMs are not a substitute for verification and cannot be treated as a compliance judgment. So if submissions are restricted, and no central body is validating their accuracy, critics see the outlines of a system that can display transparency without fully delivering it.

The Realist’s Eye

Restricted does not automatically mean deceptive

That darker reading has limits. Governments do not need sinister motives to restrict a filing. Biological infrastructure can expose sensitive details about national biodefense work, public-health readiness, industrial capacity, and supply-chain vulnerabilities. A state might reasonably conclude that sharing such information with other treaty members is acceptable while publishing it openly to the whole world is not. The public is not the only audience the treaty was built for; the legal relationship is among States Parties.

There is another complication. Some CBM material may already be partly available elsewhere—in public health reporting, national legislation databases, WHO channels, or domestic regulatory filings. That means a “restricted” label does not always convert the underlying reality into a secret. In some cases, restriction may hide only the treaty-format packaging, not the core facts themselves.

The deeper problem may be quality, not just access

The realist also has to admit that unrestricted access alone would not solve the BWC’s confidence problem. A public report can still be incomplete, outdated, strategically vague, or technically truthful while omitting what matters most. A country can file on time and still leave major interpretive gaps around contract manufacturing, surge capacity, biodefense overlap, or how quickly civilian systems could be repurposed in a crisis. Making every CBM public would expand scrutiny, but it would not magically create verification.

That is why the strongest criticism of restricted reporting may be narrower than the broad conspiracy frame suggests. The issue is not that secrecy proves hidden weapons work. It does not. The issue is that the BWC depends on trust-building paperwork in a field shaped by dual-use science, and then allows that paperwork to operate at two visibility levels. As we argued in our earlier look at why BWC transparency reports stay hidden, that design can preserve diplomacy while leaving public confidence oddly underfed.

What We Know For Certain

• UNODA says BWC States Parties must submit annual CBM reports by 15 April covering the previous calendar year.
• The BWC CBM system covers six measures: A, B, C, E, F, and G.
• UNODA states that governments may make CBM submissions publicly available or restrict them to other States Parties only.
• The BWC has no standing verification organization comparable to the OPCW.
• The public UN CBM portal explicitly notes that non-registered users can search only publicly accessible CBM reports.

The Unanswered Questions

• How many governments keep CBM reports restricted by habit rather than a fresh policy decision?
• Would partial-publication options increase transparency without exposing genuinely sensitive biodefense information?
• How often do States Parties actually use restricted CBMs to question one another’s filings or request clarification?
• If the public cannot review many submissions, who outside governments meaningfully pressure-tests the system’s accuracy?

The Closer — You Decide

Sometimes the unsettling part is not what a treaty hides. It is what a treaty openly admits it can hide. The BWC’s confidence-building measures are real. The reporting deadlines are real. The option to keep those reports inside a smaller circle is real too. Maybe that is prudent statecraft. Maybe it is the kind of managed opacity that lets a weak system survive without ever becoming fully convincing. Either way, the paperwork exists, and so does the blind spot. The evidence is on the table. You decide.

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