Employees and/or functional managers increasingly adopt and use IT systems and services that the IS management of the organization does neither provide nor approve. To effectively counteract such shadow IT in organizations, the understanding of employees’ motivations and drivers is necessary. However, the scant literature on this topic primarily focused on various governance approaches at firm level. With the objective to open the black box of shadow IT usage at the individual unit of analysis, we develop a research model and propose a laboratory experiment to examine users’ justifications for violating implicit and explicit IT usage restrictions based on neutralization theory. To be precise, in this research-in-progress, we posit positive associations between shadow IT usage and human tendencies to downplay such kind of rule-breaking behaviors due to necessity, no injury, and injustice. We expect a lower impact of these neutralization effects in the presence of behavioral IT guidelines that explicitly prohibit users to employ exactly those shadow IT systems.