As a Certificate is a credential the Registration Authority SHOULD perform the same as for Credential Enrollment.
The Registration Authority is responsible for assurance that Identity Proofing that the Requesting Party is the appropriate entity for the certificate is will be used to represent.
The Registration Authority must provide the proper Certificate Level Of Assurance and perform the proper Identity Proofing associated with each Certificate Level Of Assurance
The Registration Authority is responsible for the certificate issuance but the Certificate Authority is Accountable