A tort is a violation of rights of an identifiable individual or business that has been wronged intentionally or by negligence. Common torts include defamation, nuisance, conversion, and negligence. A wide variety of tort actions can occur on property. For example, a visitor to the property could slip and fall in the driveway due to rain or snow on the ground and sue the landlord and tenant for damages. A pet dog could bite the mail carrier or a neighbor's child chasing a ball through the front yard, which would result in medical bills and other damages that could be litigated. Liability means legal responsibility for something. Some torts may be assessed against the landlord, while others are the responsibility of the tenant. Torts can also be committed by and against a wide variety of parties. Torts may be by the landlord against the tenant and vice versa, or they may involve actions by visitors to the property against the property occupiers.
In general, most tenants in a residential or commercial lease are responsible for injuries that happen on the premises during the term of the lease. Often the lease will spell out insurance requirements for these specific purposes. Tenants, particularly in commercial lease situations, usually must have insurance up to a certain amount payable for damages that lists the landlord as a party to be defended in any tort action lawsuit. For example, suppose a tenant is running a store, the floors get wet, and a customer slips and falls. The tenant, not the landlord, would be responsible through their insurance policy for the potential injury. Similarly, if an invited guest to the home is bitten by the tenant's dog, then that responsibility is with the tenant and their insurer, not with the landlord.
However, the landlord is responsible for injuries that happen in the common area (space such as shared pools, gyms, multipurpose meeting rooms, and external pathways connecting units) over which the tenant has no control or responsibility. If a person slips and falls in an apartment complex's icy, unsalted parking lot, then the landlord would be the responsible party for the injury. In general, it is the duty of the landlord to maintain surface lots.
Landlords may be held responsible for crimes that happen on the premises if the courts decide that the landlord could have acted to prevent the crime. Considerations would be the nature and type of crime, how foreseeable it was by looking at how common crime is in the general area, and whether a reasonable person would conclude that the landlord could have prevented the crime. For example, in an apartment complex, landlords are required to provide doors with locks on them, usually at least a deadbolt lock, to secure each individual apartment unit. Mailboxes are usually accessible via a lock that can be opened with a key as well. If a tenant is a victim of a crime due to the landlord failing to provide adequate safety and locks upon the property, the tenant could sue the landlord for the resultant damages. Still, a tenant would probably have to maintain their own rental insurance policy to recover damages if the tenant is burglarized and has items stolen.