Syntactic impairments in aphasia can provide a powerful window into the neurobiology of language. Considerable research has focused on agrammatism in nonfluent aphasia, driving a strong association between frontal brain systems and syntax. However, the syndrome of paragrammatism, typically characterized by grammatical errors in fluent aphasia, has recieved far less attention. Recent work has suggested that paragrammatism is primarily associated with posterior temporal-parietal lesions, converging with functional neuroimaging evidence that these regions support hierarchical syntax. However, the holistic perceptual approaches to paragrammatism used in this work suffer from limited inter-rater reliability as well as conflating factors such as speech rate. To remedy these issues, this study reports a system to classify agrammatic and paragrammatic symptoms at the level of the utterance using an objective coding scheme, building on previous analyses by Matchin et al. (2020). Trained speech-pathology students rated transcriptions of 88 retellings of the story of Cinderella from persons with aphasia alongside transcriptions from 53 age-matched healthy controls. Each utterance was classified by the presence of errors corresponding to functional processing (i.e., hierarchical processing) or positional processing (i.e., linearization), along with non-grammatical errors. We found that patients defined holistically using the perceptual approach as agrammatic or paragrammatic doubly dissociated in rates of functional and positional processing, and that qualitative behavioral variables distinguish healthy speech from agrammatic and paragrammatic samples. We suggest that agrammatism and paragrammatism result from distinct breakdowns in syntactic structure building during speech, resulting from damage to distinct syntactic subsystems of the brain.