All 50 states and the District of Columbia have some type of Good Samaritan law. 

The details of Good Samaritan laws vary by jurisdiction, including who is protected 

from liability and under what circumstances.

Generally speaking, these laws prevent a rescuer who has voluntarily helped

a stranger in need from being sued for wrongdoing.

A Good Samaritan acts in good faith (not for reward of any sort).

You are generally protected from liability as long as you act "as a reasonable and prudent person 

would in the same or similar circumstance".

A "reasonable and prudent person" would introduce himself, ask permission

to give care, work up to his level of training, move the person only if the scene becomes unsafe, 

you need to get to someone who is more seriously injured or in order to provide proper care, 

check the person for "life threatening" illness or injury, Call 9-1-1 if needed, 

and continue to give care until advanced medical care can take over for you.

A couple of things to keep in mind -

Standard of care. This is the level of emergency care that you are expected

to provide, based on the level of your training, and with a response that

a reasonable person in the same circumstances would use.

If a person’s actions do not meet this standard, then the acts may be considered negligent, 

and any damages resulting may be claimed in a lawsuit for negligence.

Negligence. This occurs when an injured or ill person incurs proven damage from a trained person 

who has a duty to act and the person does not uphold the standard of care.

Confidentiality. A person has the right for his name and medical history

to remain confidential among care providers. Only share information you have received 

from the victim with the 9-1-1 operator, the EMS crew or Law Enforcement who arrive 

on scene to take over for you.

The regulation in the United States that governs confidentiality is the Health Insurance Portability 

and Accountability Act, which is commonly referred to as the HIPAA law.