Strange nominative case in topicalized object pronominal relative clauses

In an online production experiment, we investigated the effect of sentence position on the preference for either a nominative or object form of an object pronoun restricted by a relative clause in Dutch. Results show a significant preference for the nominative form of the restricted object pronoun in sentence-initial position as it was chosen in 95% of the cases. In the original object position this percentage is only 20%. The preference for a nominative pronominal object is considered a grammatical norm violation. We account for this in terms of a combination of two factors. First, the presence of the relative clause makes the object ‘long’. Second, the sentence-initial position is a syntactic position that is relatively far removed from the original object position. We argue that when a long object is topicalized, there are too many intervening elements between the pronoun and the verb of which it is the complement. If the distance between the pronominal object and the verb has become too long, the object case fades from the working memory. This then results in the appearance of nominative case as the default case for topicalized object pronominal relative clauses in Dutch.