Evidence lock (explained)

Available functionality depends on the system you are using. See Product comparison chart for more information.

With the evidence lock functionality, client operators can protect video sequences, including audio and other data, from deletion if required, for example, while an investigation or trial is ongoing. For information about how to lock evidence, see the XProtect Smart Client documentation.

When protected, the data cannot be deleted, neither automatically by the system after the system's default retention time or in other situations nor manually by the client users. The system or a user cannot delete the data until a user with sufficient user rights unlocks the evidence.

Flow diagram for Evidence Lock:

1. User creates an evidence lock in XProtect Smart Client. Information sent to Management Server.
2. Management Server stores information about the evidence lock in the SQL server.
3. Management Server informs Recording Server to store and protect the protected recordings in the database.

When the operator creates an evidence lock, the protected data remains in the recording storage that it was recorded to, and is moved to archiving disks together with non-protected data, but the protected data:

• Follows the retention time configured for the evidence lock. Potentially infinitely.
• Keeps the original quality of the recordings, even if grooming has been configured for non-protected data.

When an operator creates locks, the minimum size of a sequence is the period that the database divides recorded files into, this is by default one-hour sequences. You can change this, but it requires that you customize the RecorderConfig.xml file on the recording server. If a small sequence spans two one-hour periods, the system locks the recordings in both periods.

In the audit log in the Management Client, you can see when a user creates, edits or deletes evidence locks.

When a disk runs out of disk space, it does not impact the protected data. Instead the oldest non-protected data will be deleted. If there are no more non-protected data to delete, the system stops recording. You can create rules and alarms triggered by disk full events, so you are automatically notified.

Except for more data being stored for a longer period and potentially affecting disk storage, the evidence lock feature as such does not influence system performance.

If you move hardware to another recording server:

• Recordings protected with evidence locks, remains on the old recording server following the retention time set for the evidence lock, when it was created.
• The XProtect Smart Client user can still protect data with evidence locks on the recordings that were made on a camera before it was moved to another recording server. Even if you move the camera multiple times and the recordings are stored on multiple recording servers.

By default, all operators have the default evidence lock profile assigned to them but no user access rights to the feature. To specify the evidence lock access rights of a role, see the Device tab for role settings. To specify the evidence lock profile of a role, see the Info tab for role settings.

In the Management Client, you can edit the properties of the default evidence lock profile and create additional evidence lock profiles and assign these to the roles instead.

Evidence Lock under System Dashboard shows an overview of all protected data on the current surveillance system:

• start and end date for the protected data
• the user who locked the evidence
• when the evidence is no longer locked
• where the data is stored
• the size of each evidence lock

All information shown in Evidence Lock are snapshots. Press F5 to refresh.

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