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Revision as of 23:30, 21 December 2008 by Soulweaver(talk | contribs)(better quality; not removing the bad pic tag 'cause the main picture is still unsatisfactory)
The first time one appeared was in The Case of the K-9 Caper. In that episode, Ash and his friends met up with an Officer Jenny who trained Growlithe to act as police dogs.