A fusion approach is proposed for improving the efficiency of writer verification systems. A short handwritten sentence is employed for this purpose. Each word of the sentence is used to tackle an individual verification problem. Then, the word-level (local) decisions are fused in order to obtain a more reliable global decision by means of the Neyman–Pearson approach. The correlation of the local decisions is extensively studied and incorporated in the fusion procedure by means of the Bahadur–Lazarsfeld expansion series. A database containing 4800 sentences is employed to validate the performance of the method. The improvement in verification performance is due to both the fusion procedure applied and the full discretion of the writer to choose his own secret word.