In Cooper v. United States (4th Cir. 1979), 594 F.2d 12, the court held that the defendant had a right to compel specific performance of an unconsummated plea bargain as a matter of fundamental fairness within substantive due process guarantees of the fifth amendment and under the sixth amendment right to effective assistance of counsel. The court in Cooper concluded that there were seven factual elements crucial to its finding that defendant's constitutional rights to substantive due process had been violated. These factors were as follows: The proposal was specific and unambiguous in form, and was made without any reservation related to a superior's approval or otherwise; its content was reasonable in context; it was made by a prosecutor with apparent (and probably actual) authority at that time; it was communicated promptly to the defendant so that no question of staleness was involved; the defendant assented promptly and unequivocally to its terms, indicated his assent to his counsel, and was entitled so far as the record shows to assume that its communication to the government would consummate the plea agreement; defense counsel did in fact within a matter of a few hours communicate defendant's acceptance to the government by sheer fortuity being told of the government's 'withdrawal' before he could vocalize his client's 'acceptance'; and finally, the reason for the attempted withdrawal had nothing to do with extenuating circumstances affecting the government's or any public interest that were unknown when the proposal was extended . . . ."