If you or a family member has been hurt because a landlord ignored repeated warnings about a dangerous tenant or a tenant's guest, do not assume nothing can be done because the person who hurt you was not the property owner. California law holds landlords responsible for injuries caused by third parties when the landlord knew, or should have known, about the danger and failed to act. The duty starts with the ordinary duty of care every landowner owes under Civil Code section 1714, and courts examining landlord liability for third-party crime, including Delgado v. American Multi-Cinema, weigh how foreseeable the harm was against how easy it would have been to prevent. Where the remedy was as simple and inexpensive as enforcing an existing lease term against a known dangerous individual, a landlord cannot credibly argue that acting would have been an unreasonable burden. Ask whether other tenants complained about the same person before you were hurt, and whether the lease or house rules gave the landlord authority to remove that person that the landlord simply never used. Those details are often the foundation of the strongest cases.