An affidavit certificate is a sworn statement in written format made under an affirmation or oath before a Magistrate or authorized officer. In simple terms, it is a declaration of facts made in writing and sworn before a person who has the authority to administer oaths
https://www.google.com/search?ie=UTF-8&client=ms-android-sam...

> feasibly an oath of duty or of (military or political etc.) offiice. We never had to swear an oath at our London export offices as all of us export clerks and managers / manageresses had been honest.

BTW, aAt UK (and Aussie) Solicitors' Firms I know, members ask each other whether they, as Commissioners for Oaths, would 'like to do some swearing', notably to depose to the truthfulness and veracity of each other's Solicitors' Undertakings or to authenticate each other's signatures,

The transport staff is sworn, I think it is a card that certifies belonging to the transport company mentioned.

This "carte d'assermentation" is more than an ordinary "company ID", it's in effect a "proof of authority" to conduct ID checks on passengers.

The nearest to it would be a "warrant card" - usually associated with police but can be given to other profession with similar powers.

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Note added at 2 days 8 hrs (2023-07-22 21:39:28 GMT)
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CONTROLES D'IDENTITE DANS LES TRAINS SNCF
Publié le 03/10/2013
Par Le BLOG de Maître Muriel Bodin, avocate
Vu 100 420 fois 84

plusieurs questions m'ont été posées sur la légalité des contrôles d'identité dans les trains SNCF par des contrôleurs ou par des agents RATP. Or, le Code de Procédure pénale réserve ce droit, article 78-1, aux officiers de police judiciaire, agents de police judiciaire et agents de police judiciaire adjoints. Qu'en est il du contrôleur SNCF ou de la RATP dans ce cas là?

https://www.legavox.fr/blog/maitre-muriel-bodin/controles-id...

this is far more than simply "checking tickets".


A warrant card is proof of identification and authority carried by police officers and some other law enforcement officers including immigration officers. The term is normally used only within the United Kingdom and in current and former Commonwealth countries. Many other countries refer to their equivalent of warrant cards simply as police credentials, commission books, or identification cards. In the UK MI5 officers also have warrant cards.[1] Specially trained mental health practitioners called Approved Mental Health Professional are also warranted council officers and carry warrant cards when acting under the Mental Health Act 1983.[2]
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United Kingdom
In the United Kingdom, a warrant card is evidence of a constable's sworn attestation.
https://en.wikipedia.org/wiki/Warrant_card


In British legislation, an oath taken by a constable in England and Wales or in Northern Ireland is described as an "attestation" and annotated as such in a relevant Act. In Scotland a constable is required to make a "declaration".
https://en.wikipedia.org/wiki/Police_oath#United_Kingdom