(concurring) — I concur specially to emphasize the unit of prosecution approach to double jeopardy is necessarily one that must develop on a case-by-case basis. There may be circumstances in future cases where the jurisdictional or temporal differences in the possession of illegal substances may be so great as to suggest completely distinct units of prosecution. For example, if a person were arrested in Seattle for possessing 20 grams of marijuana, and Spokane police served a search warrant on the person’s Spokane residence and found 15 grams of marijuana on that same day, two distinct units of prosecution might exist. Similarly, if a person were in possession of 20 grams of marijuana and used the substance in its entirety, and, thereafter, several days later acquired another 15 grams of *641marijuana for personal use, two distinct units of prosecution are likely present under such circumstances.
The unit of prosecution approach to analyzing double jeopardy is appropriate, but is not completely without difficulty in its application. Compare, Bell v. United States, 349 U.S. 81, 75 S. Ct. 620, 99 L. Ed. 905 (1955), and Ebeling v. Morgan, 237 U.S. 625, 35 S. Ct. 710, 59 L. Ed. 1151 (1915). We must be sensitive to different factual patterns in utilizing the unit of prosecution approach to determine if there is multiple punishment for purposes of the double jeopardy clause.