Presidential impact may be influenced by such factors as the executive's desire to base appointments primarily on ideological criteria; the number of judges he is permitted to appoint; the degree to which he can use his political skills in support of his nominees; and the nature of the judicial climate into which the new judges enter. The empirical data we compiled on the voting behavior of the various presidential appointees demonstrates that federal district judges appointed by Democratic presidents were comparatively more liberal than those chosen by Republican presidents. Our findings also indicate that politically powerful presidents who showed a personal interest in their district court selections had a greater impact on the judiciary than presidents who lacked the will, the opportunity or the power to pack the judiciary. Tables, 57 notes, and appended case types are provided. (Author abstract modiefied)