who holds the privilege when it concerns attorney-client communication
Attorney–client privilege In the law of the United States, attorney–client privilege or lawyer–client privilege is a "client's right privilege to refuse to disclose and to prevent any other person from disclosing confidential communications between the client and the attorney."[1]
Miranda warning The circumstances triggering the Miranda safeguards, i.e. Miranda warnings, are "custody" and "interrogation". Custody means formal arrest or the deprivation of freedom to an extent associated with formal arrest. Interrogation means explicit questioning or actions that are reasonably likely to elicit an incriminating response. Suspects in "custody" who are about to be interrogated must be properly advised of their Miranda rights—namely, the Fifth Amendment right against compelled self incrimination (and, in furtherance of this right, the right to counsel while in custody). The Sixth Amendment right to counsel means that the suspect has the right to consult with an attorney before questioning begins and have an attorney present during the interrogation. The Fifth Amendment right against compelled self incrimination is the right to remain silent—the right to refuse to answer questions or to otherwise communicate information.