According to CNN, he was apprehensive about talking to investigators about the night because he didn't want to sound like a "crazy person."
Dalton, 45, shot multiple people on February 20 in between picking up clients who were using Uber's ride sharing service. He was charged with six counts of murder. Two other people were injured.
He told investigators that the company's mobile app made him "like a puppet" and that it would "take over your whole body," according to documents released Monday and published by WDIV.
"I asked Dalton why he was carrying his firearm tonight and he said that the Uber app literally took over his body and mind," the documents read. "Dalton explained that when the (Uber) symbol turns to black, it literally has control over you."
Dalton, who does not have a history of mental health issues, will undergo a psychiatric evaluation to determine his competence to stand trial.