In this paper I argue that Russian is a [-multiply filled Spec,CP] language: in Russian multiple wh-questions only one wh-word appears in Spec,CP, the rest are adjoined to IP. However, unlike other [-multiply filled Spec,CP] languages, Russian exhibits
Superiority effects, which, according to Rudin (1988) are characteristic of [+multiply filled Spec,CP] languages, but not of [multiply filled Spec,CP] ones. I show that, given a few assumptions, the Russian data can be accounted for by the Weak Crossover
Principle which was used by Hornstein (1995) to explain Superiority effects in a number of languages. To the extent that the analysis is successful, it provides evidence that a [-multiply filled Spec,CP] language can be subject to the Superiority Condition.