Is wiretapping appropriate to wiretap a telephone used by drug dealers?

7 The government seems to argue that wiretapping is appropriate because drug dealers often use the telephone at "irregular" or "unusual" hours. But this observation is germane to most forms of criminal activity that involve more than one willing participant and require some degree of planning. Without question, it would be in some sense more efficient to wiretap whenever a telephone was used to facilitate the commission of a crime. But the statutory requirement that other investigative procedures be exhausted before wiretapping reflects a congressional judgment that the cost of such efficiency in terms of privacy interests is too high. See United States v. Kalustian, 529 F.2d 585, 589 (9th Cir.1975).