If someone suffers an injury on your property, you hold general liability for that injury. That person could take you to court for payment of medical bills and other expenses related to the incident.
However, there are some situations in which you may not hold liability. According to California Legislative Information, the involvement of alcohol can change liability rules.
General rule
You are responsible for injuries on your property that result from your negligence. This means, for example, if you have broken stairs and someone falls on them and suffers a broken leg, you would be liable for that injury and its related expenses.
It also includes incidents that occur because of your lack of care, such as injuries from a fall on ice outside your home, which happens because you failed to clear the ice.
Exception
There is an exception to the general rule when it comes to alcohol. Even if you furnish alcohol to visitors, they remain responsible for whatever happens to them while under the influence. For example, if someone suffers a fall due to their drunken state, you are not liable.
There is an exception to the exception, though. When it comes to alcohol, you only get a liability pass if the people drinking are adults. If the person is a minor, then you are completely liable for any injuries to them even if they result from drunkenness.
Do note that for you to not have liability in situations related to alcohol, you will have to show that the alcohol was the leading factor in the incident.