If they jointly possessed it, then yes. The issue will be factual, rather than legal--does the evidence show that they (1) both paid for the bag or (2) intended to split it or (3) were both controlling the bag or (4) etc. That fact that it's a single dime bag does not mean that it had to be possessed by one person or another, not both.The people who are or who may be charged should get a criminal defense attorney to advise and represent them. In the meantime, they should not speak with the authorities, exercising their constitutional right against self-incrimination, until such time as they have the chance to speak with their attornney(s). (They may each want their own attorney, since it's possible, even likely, that their interests will diverge at trial.)