ידינו לא שפכו את הדם הזה ועינינו לא ראו… (שופטים כא:ז)

The Ibn Ezra zt”l explains that if one finds a dead person near a city, it is a sign that there is sin in that city since such a thing couldn’t have happened otherwise. The passuk says: “ידינו לא שפכו” – since the killer is not from our city, how come the dead person was found near our town?  The answer is in the next part of this passuk: “ועינינו לא ראו” – because we did not watch out and were not careful about the actions of our townspeople and therefore, such an incident occurred near us.