The electrochemical response of electrodeposited polyaniline is shown to depend strongly upon the pH of the deposition solution. The concentration of anion present during deposition has only a weak effect. When the pH of the deposition solution is less than 1.0, the response is typical of the para-substituted phenyleneamineimine structure. When the pH of the deposition solution is greater than 1.0, an additional voltammetric wave appears, and the response is a function of the dopant anion. Infrared spectroscopy was used to examine the structural properties of these films directly in situ. While films that displayed voltammetry typical of the para-substituted compound decomposed to form p-benzoquinone at high positive potentials, films displaying atypical voltammetry did not show evidence of p-benzoquinone decomposition products. Spectral analysis indicates that cross-linked structures may be important in determining the anion-dependent voltammetric response. Further, investigations into the nature of bonding in the polymer-dopant complex revealed a weak ionic interaction.