How do I figure out who is responsible for such an injury?

This will often require a detailed investigation by an attorney experienced in such cases.  We have represented a number of individuals who have been injured or even attacked at various hotels, malls, and even their own apartment complexes.  Companies and individuals that operate such premises are required to do so with an eye on potential harm that could come to their patrons.  We routinely see apartment complexes where the management knows that criminal activity is taking place there and does not warn their own tenants and guests of their tenants how to avoid being a victim of such a thing.  Similarly, many area malls can be magnets for criminal activity.  The mall owners know this, often the merchants know this but the shoppers are exposed to this without warning.