Long-range dependencies often pose problems for SRL models; in fact, special networks like GCN  and PathLSTM (Roth and Lapata, 2016) have been proposed to explicitly percolate information from each word in the sentence to its syntactic neighbors.
pathLSTM performs worse than a vanilla BiLSTM model in the case of longdistance arguments, and the performance of an SRL model augmented with GCN also decreases when more than one GCN layer is stacked.