Any person claiming title to land may convey his interest in the same, notwithstanding there may be an adverse possession thereof.
D.C. Code § 42-305
Severance of joint tenancies: This section and § 42-301 do not supersede the common law rule authorizing the unilateral severance of joint tenancies. Estate of Gulledge, App. D.C., 673 A.2d 1278 (1996).