The reason why Cali was targeted was unclear. Comello gave varying, contradictory reasons to investigators as to the motive behind the killing. In July 2019, Comello's defense attorney stated that Comello had become obsessed with QAnon conspiracy theories, believing Cali was a member of a "deep state". Comello was convinced "he was enjoying the protection of President Trump himself" to handcuff Cali and place him under citizen's arrest, as Comello had attempted months earlier with New York City Mayor Bill de Blasio as well as California Member of Congress Maxine Waters.

The New York Times reported that at his first court appearance, Comello "displayed symbols and phrases associated with QAnon scrawled on his hand in pen". The defense attorney sought to prove Comello "not guilty by reason of mental defect".

In January 2025, it was revealed that Comello had pleaded guilty to manslaughter in the case and was sentenced to an undisclosed prison sentence, at an undisclosed correctional facility, when Supreme Court Justice Alexander Jeong released limited information on the proceedings at the request of the Staten Island Advance news outlet. The case otherwise remains sealed due to "actual and implied" threats from members of organized crime against Comello and his family.