The definition of a bystander

The percentage of people who would intervene if no one else was around

If bystanders don't see other people getting involved, then they may convince themselves they shouldn't either

Ashey witnesses an aggressor using hate speech towards Sam. Ashley later decides to check up on Sam by asking her, "Is there anything I can do? Would you like to have a cup of coffee with me" to intervene by informing the authorities about the hostile situation.

The definition of an active bystander

The percentage of bystanders present in national victimizations that occur

Bystanders are less likely to get involved as the amount of people present increases because they feel like "someone else" will help

David witnesses a group of teenagers robs another teen as he waits for the train. David decides to intervene by informing the authorities.

The definition of the bystander effect

The likelihood that one person would intervene, when there are four or more people present during a distressful situation

Bystanders become fearful of emotional or physical harm from the perpetrator

Tiffany witnesses one of her friends being harassed at a party by a perpetrator. Tiffany decides to intervene by distracting the perpetrator and asking her friend to help her look for her car keys.

The factor that is said to contribute to the bystander effect

Bystanders have trouble interpreting the situation

AJ witnesses an aggressor "cat-calling" out to people as he sits on a bench at a park. AJ directly intervenes by telling them to stop and by informing them of their crude behavior.

The murder case that birthed the term "bystander effect"

Bystanders believe they don't have the strength or skills needed in order to help