You are a member of a gang & you have been arrested with another member of your gang.Both of you are confined away from each other and you have no way of communicating with other member.The police does not have enough evidence to convict both of you with major charges & instead offer you and the other member a bargain.
You have 2 choices :
A) you have remain silent
B) Or betray other member & testify that he has committed the crime.