I suggest that one way to address these issues is to ask why a customary practice ought to be law. That is, is there some non-arbitrary justification for ascribing binding effect to a general and consistent practice? Perhaps the most plausible answer to this question is Professor Starke's Recurrence of the. . practice tends to develop an expectation that, in similar future situations, the same conduct or the abstention therefrom will be repeated that the conduct or the abstention therefrom is a matter both of right ando ates When this expectation evolves further into a general acknowledgment by states obligation, the transition. . to custom may be regarded as consummated If, then, the rationale for treating custom as law is that states ought to be able to rely on the assumption that other states will behave in the future as they have in the past, it would seem to follow that behavior would count as practice if it is of a sort as would give rise to reasonable expectations that it would be followed in future similar situations. Further, if an act which would, other things equal, give rise to such expectations, is contradicted by behavior which is a better predictor of future action, it would seem that it would be unreasonable to expect that future conduct would conform to the act rather than to the contradictory behavior These considerations facilitate addressing a particularly important issue in connection with CIL: what effect on that body of law should be accorded to actions which may be seen as proxies for behavior? For example, suppose State A announces that it feels constrained by CiL to behave in accord with Rule X. Standing alone, that announcement may well support a reasonable expectation that State A will abide by rule X in the future, and should count as an item of practice supporting the existence of rule X. However, if it is clear that State a in fact systematically violates Rule x, it would seem that the net effect of State As actions is to 14 J.G. Starke, INTRODUCTION TO INTERNATIONAL LAW 38-39(10th ed 1989)7 14 J.G. Starke, INTRODUCTION TO INTERNATIONAL LAW 38-39 (10th ed. 1989). I suggest that one way to address these issues is to ask why a customary practice ought to be law. That is, is there some non-arbitrary justification for ascribing binding effect to a general and consistent practice? Perhaps the most plausible answer to this question is Professor Starke’s: Recurrence of the . . . practice tends to develop an expectation that, in similar future situations, the same conduct or the abstention therefrom will be repeated. When this expectation evolves further into a general acknowledgment by states that the conduct or the abstention therefrom is a matter both of right and of obligation, the transition . . . to custom may be regarded as consummated.14 If, then, the rationale for treating custom as law is that states ought to be able to rely on the assumption that other states will behave in the future as they have in the past, it would seem to follow that behavior would count as practice if it is of a sort as would give rise to reasonable expectations that it would be followed in future similar situations. Further, if an act which would, other things equal, give rise to such expectations, is contradicted by behavior which is a better predictor of future action, it would seem that it would be unreasonable to expect that future conduct would conform to the act rather than to the contradictory behavior. These considerations facilitate addressing a particularly important issue in connection with CIL: what effect on that body of law should be accorded to actions which may be seen as proxies for behavior? For example, suppose State A announces that it feels constrained by CIL to behave in accord with Rule X. Standing alone, that announcement may well support a reasonable expectation that State A will abide by Rule X in the future, and should count as an item of practice supporting the existence of Rule X. However, if it is clear that State A in fact systematically violates Rule X, it would seem that the net effect of State A’s actions is to