Police cameras are not beneficial
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Police footage may be unhelpful if badly managed.
Police cameras are only as effective as they are managed. If footage is capable of being reviewed and edited, or withheld from relevant parties, this may be counterproductive to the aims of their provision.
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The power of a police camera can be misused. Whether a police camera is there to promote transparency and accountability, or whether it serves to impinge upon privacy or be used for other abusive means depends on who it is managed by, and how it is governed.  Investigations have revealed that police are unwilling to disclose material that has been recorded on police cameras that disclose that the officer engaged in excess use of force, or was involved in a shooting, often citing that the investigation is ongoing, a legal exemption.  The Met in the UK has been criticised for not releasing police camera footage. In an internal memo it is established that some of the behaviour in the footage would not put the Met Police in a pleasant light. It cited its reasons as data protection, trial by social media, and exacerbation of tensions. The refusal to release the footage has been criticised for witholding information that would convey the concerns raised by minorities for years, and for causing further public mistrust in the policing system. 
Although there has been varying degrees of discretion employed in the use of police cameras and the footage that has been disclosed since 2014, in the wake of the George Floyd and Breonna Taylor murders in 2020, the Justice in Policing Act 2020 would make it necessary for federal uniformed police officers to wear a camera promoting some uniformity. After the killing of Michael Brown in 2014, 47% of police departments were wearing cameras. There have been discrepancies on the disclosure of footage from police cameras varying from state to state, leading to inconsistencies in achieving transparency. Despite the discrepancies in disclosure, and the current concerns regarding how much discretion ought to be given to police to control the body cameras, the cameras are significant, and are one element of many in pushing towards overall transparency. 
Rejecting the premises