An approach police agencies use to combat corruption is to involve in the review process.

One approach that police agencies use to combat corruption is to involve external oversight bodies in the review process. Here are the steps:

1. Identify External Oversight Bodies: These are independent organizations that are not part of the police agency. They could be local, state, or national bodies. Examples include the Office of the Independent Police Review Director in Ontario, Canada, or the Independent Office for Police Conduct in the UK.

2. Establish a Relationship: The police agency needs to establish a working relationship with these oversight bodies. This could involve setting up regular meetings, sharing information, and agreeing on a process for the oversight body to review the police agency's actions.

3. Regular Reviews: The oversight body regularly reviews the police agency's actions. This could involve looking at records, interviewing officers, and investigating complaints.

4. Feedback and Action: After the review, the oversight body provides feedback to the police agency. This could involve recommendations for changes to policies or practices. The police agency then needs to take action based on this feedback.

5. Transparency: The results of the reviews and the actions taken by the police agency are made public. This transparency helps to build trust with the community and deter corruption.

6. Ongoing Monitoring: The oversight body continues to monitor the police agency and conduct regular reviews. This ongoing process helps to ensure that the police agency stays accountable and that any issues of corruption are quickly identified and addressed.