Leaders of the advocate group say they learned of those payments - that are made after successful prosecutions - from a public records request.
They also alleged discrimination by Durham police in the way drug checkpoints and undercover drug busts are set up in black neighborhoods.
"However noble the department's motives may be, the practice of using license checkpoints to enforce drug laws is strictly and unambiguously unconstitutional," said Ian Mance with the SCSJ.
The Durham Police Department responded with a statement of its own Wednesday:
The Durham Police Department denies any unethical or illegal activity as it relates to the paying of bonuses to confidential informants. The Police Department has never paid for convictions, only cooperation through case completion.
However, we are asking our police attorney to review our practices and we will be in discussion with the District Attorney's office to ensure that there are no procedural or legal issues in how we handle informants and their payment.