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We consider a model where large number of data items, each with different access privileges for a set of users, is outsourced and access is to be granted according to the access control policy specified by the data owner. Given this scenario and security goals, we highlight severe trust issue in existing proxy re-encryption schemes that are extensively used for access control in cloud computing. Typically, using proxy re-encryption schemes, access is managed through delegation of decryption rights from data owner to a user. In traditional proxy re-encryption schemes, availability of a re-encryption key from a delegator to a delegatee guarantees access delegation irrespective of delegatee’s access privileges for different data items encrypted under the delegator’s public key. So, employing a re-encryption scheme trivially for access control on outsourced data demands questionable amount of trust on the re …