新型コロナワクチン健康被害と情報の非対称性

1. はじめに

新型コロナウイルス感染症対策をめぐっては、医科学コミュニティにおいて概ね成功したとする受け止めと、法学コミュニティにおいて人権・法治国家の原則から看過しえない問題を残したとする受け止めとの間に、無視しえない乖離がある。とりわけワクチンをめぐって、この乖離は大きい。本稿は、この乖離を、医学と法学がともに「因果関係」という同じ語を用いながらその内実を異にしてきたという一点に絞り込み、法学の側からの架橋を試みるものである。

2. 「証明の難しさ」は自然の限界ではない

従来の薬害訴訟を阻んできた証明の困難は、科学が未解明という「自然の限界」として理解されてきた。しかし新型コロナワクチンの事態はこの前提を覆す。救済を阻むのは自然の限界ではなく、安全性データの秘匿、市販後監視の機能不全という、人為的に維持された構造である。検証可能なデータを生成しない不作為によって「不明」が維持されているのなら、それは是正されるべき制度の欠陥である。

3. 「比例原則」が救う、情報の持たざる者

情報を圧倒的に支配する側と持たざる側との非対称な関係では、「比例原則」が優位者の行為を厳格に制約する。統制対象は、操作不可能な生物学的因果の連鎖そのものではなく、それをいかなる証拠で認定するかを選ぶ「裁判官の評価行為」である。決定的映像を独占する側に有利な基準を設ける審判が不公正であるように、情報を独占する国・企業に対してのみ厳密な立証を要求し続けることは、評価行為自体が比例原則に反する。

4. 医療・介護従事者の「断りにくさ」

職務上の接種を事実上要請された医療・介護従事者の事案は深刻である。形式上は任意でも、同調圧力や職業倫理により実質的な「断りにくさ」が制度的に作り込まれていた。これによる健康被害は業務に内在する危険の現実化であり、私的選択として切り捨てれば労災補償の理念が空洞化する。因果関係の証明は100％の確実性を要さず、経験則上の高度の蓋然性で足りる（ルンバール事件）。立証負担の放置は、司法の不作為にほかならない。

5. 年齢による「便益と侵害」の逆転

回避された死亡の約9割は60歳以上に集中し、若年層の絶対的リスク減少はわずか0.84ポイント（接種必要数119回）に留まる一方、若年男性では心筋炎という重大なリスクが現れている。治験時の「相対リスク減少95％」が、年齢で劇的に変動する絶対的リスクの実態を覆い隠し、全年齢一律の推進を正当化してきたことの当否が問われる。便益の薄い層に侵害を課した以上、正当化責任は情報を保持していた側が負う。

6. 国家の「検証義務」

国は過小保護の禁止に基づき、原因究明の制度基盤を整備する検証義務を負う。データがないから検証できないのではなく、データを整備しないこと自体が不作為の違法である。要請されるのは、①個人単位の追跡可能なデータ基盤、②独立した調査機構、③責任追及から切り離された調査結果の担保、の三要素である。

責任の概念を「犯人探し」から、構造的優位者が負うべき「リスク帰属」へと再定位しなければならない。比例原則や検証義務は、情報の壁に守られた沈黙を打破する武器であり、法的救済を国家の慈悲による給付ではなく、優位者の当然の責務として位置づけ直すことが求められている。

（これは、日本産業保健法学会第６回大会における報告「新型コロナワクチン健康被害と情報の非対称性」を要約したものである。https://jaohl.info）

English

1. Introduction

In the response to the COVID-19 pandemic, a significant gap has opened between how the medical-science community and the legal community have come to see it: the former largely regards the response as a success, while the latter sees it as having left problems that cannot be overlooked from the standpoint of human rights and the rule of law. This gap is especially wide when it comes to the vaccine. This paper narrows that gap down to a single point — that medicine and law have long used the same word, "causation," while meaning different things by it — and attempts a bridge from the side of law.

2. The "Difficulty of Proof" Is Not a Limit of Nature

In past cases of drug-induced injury, the difficulty of proving causation has long been understood as a kind of "epistemic limit imposed by nature" that science had simply not yet resolved. The situation surrounding the COVID-19 vaccine overturns that premise. What is blocking redress here is not a limit of nature, but a structure that has been artificially maintained — through the concealment of safety data and the dysfunction of post-marketing surveillance. If "uncertainty" is being sustained by an omission that fails to generate verifiable data, then it is a defect in the system that must be corrected.

3. The "Principle of Proportionality" Rescues Those Without Information

In an asymmetric relationship where one side holds overwhelming control over information, the principle of proportionality strictly constrains the conduct of the party in the superior position. What must be controlled is not the biological chain of causation itself, but the judge's evaluative act of choosing what evidence will establish it. Just as it would be unfair for a referee to set standards favoring whichever team controls the decisive replay footage, so too it violates the principle of proportionality to keep demanding strict proof from victims alone, while the state and manufacturers monopolize the relevant information.

4. The "Difficulty of Refusing" Facing Healthcare and Care Workers

Especially serious is the case of healthcare and care workers effectively required to be vaccinated as part of their jobs. Even where vaccination was formally "voluntary," peer pressure and professional ethics built a real, structural "difficulty of refusal" into the workplace. Health damage arising under these conditions is the materialization of a risk inherent in the work itself; treating it as a purely private choice would hollow out the basic rationale of workers' compensation. Proof of causation does not require 100% certainty — a high degree of probability is enough (the Runbar case). Leaving this burden of proof unaddressed amounts to a failure of the judiciary to act.

5. The Age-Based Reversal of "Benefit and Harm"

Roughly 90% of the deaths the vaccine is estimated to have averted are concentrated among people 60 and older, while the absolute risk reduction for younger people comes to a mere 0.84 percentage points (a number needed to vaccinate of 119) — even as young men show a clear signal of serious risk in the form of myocarditis. This raises the question of whether the "95% relative risk reduction" reported in trials was used to justify a uniform rollout across all ages, even as it obscured how dramatically the absolute risk reduction varies by age. Having imposed harm on a group that gained little benefit, the burden of justifying that falls on whoever held the relevant information.

6. The State's "Duty to Verify"

Under the constitutional prohibition on under-protection, the state bears a duty to build the institutional infrastructure needed to investigate causation. The problem is not that verification is impossible for lack of data; failing to build the infrastructure that would make verification possible is itself an unlawful omission. This requires: (1) a comprehensive data infrastructure enabling individual-level tracking, (2) an independent investigative body insulated from political influence, and (3) a guarantee that findings are kept separate from the pursuit of liability.

7. Conclusion

We must reframe responsibility — away from "finding the culprit" and toward the proper allocation of risk borne by whoever holds the structural upper hand. The principle of proportionality and the duty to verify are tools for breaking the silence that a wall of information has protected. It is time to stop treating legal relief as an act of state mercy, and instead recognize it as the rightful responsibility of whoever holds the advantage.

(This is a summary of a presentation, "COVID-19 Vaccine Health Damage and Information Asymmetry," given at the 6th Annual Conference of the Japan Association of Occupational Health Law. https://jaohl.info)