Yes, provided that he/she is allowed by the laws applicable in your country to sign a Legal Opinion on which the EPC can legally rely upon. Please note that in certain countries the local laws allow internal legal counsel to sign Legal Opinions only for the benefit of the company/institution for which they work. Please ensure with your internal legal counsel that this is not the case in your country, and, that your internal legal counsel can indeed issue a valid Legal Opinion on which the EPC can rely upon. The Secretariat may ask you to prove this (i.e., to provide the extract from the relevant local legislation officially translated into English).