If a witness's testimony relates to a matter for which the witness, personally, or a person related to the witness in any of the following ways, would likely be subject to criminal prosecution or conviction, the witness may refuse to testify. The same applies if a witness's testimony relates to a matter that would harm the reputation of these persons:
証言が証人又は証人と次に掲げる関係を有する者が刑事訴追を受け、又は有罪判決を受けるおそれがある事項に関するときは、証人は、証言を拒むことができる。証言がこれらの者の名誉を害すべき事項に関するときも、同様とする。
a person who is or was the witness's spouse, relative within the fourth degree of consanguinity, or relative within the third degree of affinity;
配偶者、四親等内の血族若しくは三親等内の姻族の関係にあり、又はあったこと。
the witness's guardian or a person under the guardianship of the witness.
後見人と被後見人の関係にあること。
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