A Philadelphia cyclist named Mary Martin intervened in a sexual assault occurring in broad daylight on 21 September, striking the alleged attacker with her bike helmet and driving him to flee. The incident highlights a case of someone overcoming the "bystander effect" to assist a victim in distress in public.

The 63-year-old victim was approached from behind and inappropriately touched near the 1800 block of Federal Street in the Point Breeze neighbourhood at approximately 4:15pm. After confronting the man and realising the direct physical confrontation put her at risk, Martin took photographs of the fleeing suspect and accompanied the victim to the Philadelphia Police Special Victims Unit to file a report. No injuries were reported. Martin attributed her decision to intervene partly to her understanding of the bystander effect, a psychological phenomenon where people hesitate to act when witnessing trouble. Police continue investigating and are appealing for help identifying the suspect using the photographs Martin provided.