Which of the following crimes could fall under accomplice liability?

Accomplice liability applies to individuals who assist, aid, or encourage another person in the commission of a crime. In this case, helping a friend plan a break-in establishes a clear connection to a criminal act. This involvement indicates that the person is not merely a passive observer but is actively contributing to the commission of the crime, which falls within the scope of accomplice liability.

The other scenarios involve actions that do not imply direct involvement in a crime by assisting or facilitating someone else's criminal behavior. Filing a false police report is a crime, but it would only involve the individual filing the report. Stealing a neighbor's property is also a standalone crime for the perpetrator without indicating any assistance from another person. Writing a letter of apology does not involve any criminal act and therefore cannot be classified under accomplice liability. The key element of planning a crime with someone else directly connects to the concept of aiding or abetting, which is why that choice stands out as the correct application of accomplice liability.