The commission may, after consultation with the director, and with or without hearing, issue a temporary or permanent certificate, except that a certificate may not be issued without a hearing over the formal objection of a person or party in possession with standing to object. The commission, after consultation with the director, may deny the application for a temporary or permanent certificate in whole or part, with or without hearing, except that such denial may not be ordered without a hearing over the formal objection of the applicant. The commission, after consultation with the director, may attach to the exercise of the rights granted by the certificate such terms and conditions as, in its judgment, the public convenience and necessity requires.