In Powell V.Texas, 392 U.S. 514 (1968), the Supreme Court dealt with alcoholism rather than drug addiction as in the Robinson v. California, 370 U. S. 660 (1962) case. The majority stated:

The entire thrust of Robinson's interpretation of the Cruel and Unusual Punishment Clause is that criminal penalties may be inflicted only if the accused has committed some act, has engaged in some behavior, which society has an interest in preventing, or perhaps, in historical common law terms, has committed some actus reus. It thus does not deal with the question of whether certain conduct cannot constitutionally be punished because it is, in some sense, "involuntary" or "occasioned by a compulsion." Page 392 U. S. 534

One law review article states: "Powell arguably represents the Court's acceptance of the position that involuntary conduct may not be punished." Valparaiso University Law Review, Vol. 4, No. 1 [1969], Art. 3, page 86. http://scholar.valpo.edu/cgi/viewcon...9&context=vulr

While Powell v. Texas court made the distinction between a public behavior and a physical condition, it did not specifically overrule Robinson.

It appears to me psychopaths may not be sanctioned criminally for their status but remain open to prosecution for their actions. Psychopathy is not recognized in the DSM. There is evidence psychopaths know right from wrong, and have the capacity to refrain from criminal conduct.