In the cryptographic literature, the term credential is used instead of hybrid certificates, but we use this term for the personal information shown by the user at registration. See the description of the certificate manager for these details. 2.1 Details about What a Certificate Means to a Recipient A certificate is a signed statement, and thus, if the recipient acts on it and later finds out that it was wrong, he can hold the signer responsible for it, as far as the responsibility indicated in the certificate goes. It is in the recipient's judgement to believe this certifier or not. In some cases, the fact that the certifier assumes responsibility is enough, but in some cases it would not help the recipient much if the certifier is punished or has to pay damages after the fact.
Someone signing a certificate only assumes responsibility for the statement signed.
In particular, someone signing a key certificate is only responsible for correct linkage between person and key, and in no way for this person's trustworthiness. But of course the passport issuer does not in any way suggest that this person has an arbitrary amount of money to back these cheques, or even assume responsibility for these cheques. Note that here we deal with the semantics of certificates, not with their internal data structure. In an implementation, someone who only signs one type of hybrid certificates, i.e., always with the same attributes, may not include the attributes explicitly. In particular, this may hold for some legacy certificates.