Added approval status section to compliance dashboard docs

This section describes what the approval status is, how it is determined
 what status is selected and what the separation of duties entails

doc/user/compliance/compliance_dashboard/index.md

@@ -17,7 +17,7 @@ for merging into production.
 
 To access the Compliance Dashboard for a group, navigate to **{shield}** **Security & Compliance > Compliance** on the group's menu.
 
-![Compliance Dashboard](img/compliance_dashboard_v13_2.png)
+![Compliance Dashboard](img/compliance_dashboard_v13_3.png)
 
 ## Use cases
 
@@ -34,3 +34,28 @@ You can use the dashboard to:
 
 - On [GitLab Ultimate](https://about.gitlab.com/pricing/) tier.
 - By **Administrators** and **Group Owners**.
+
+## Approval status and separation of duties
+
+> [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/217939) in [GitLab Ultimate](https://about.gitlab.com/pricing/) 13.3.
+
+We support a separation of duties policy between users who create and approve Merge Requests.
+The approval status column can help you identify violations of this policy.
+Our criteria for the separation of duties is as follows:
+
+- [A Merge Request author is **not** allowed to approve their Merge Request](../../project/merge_requests/merge_request_approvals.md#allowing-merge-request-authors-to-approve-their-own-merge-requests)
+- [A Merge Request committer is **not** allowed to approve a Merge Request they have added commits to](../../project/merge_requests/merge_request_approvals.md#prevent-approval-of-merge-requests-by-their-committers)
+- [The minimum number of approvals required to merge a Merge Request is **at least** two](../../project/merge_requests/merge_request_approvals.md#approval-rules)
+
+The "Approval status" column shows you, at a glance, whether a Merge Request is complying with the above.
+This column has four states:
+
+| State | Description |
+|:------|:------------|
+| Empty | The Merge Request approval status is unknown |
+| ![Failed](img/failed_icon_v13_3.png) | The Merge Request **does not** comply with any of the above criteria |
+| ![Warning](img/warning_icon_v13_3.png) | The Merge Request complies with **some** of the above criteria |
+| ![Success](img/success_icon_v13_3.png) | The Merge Request complies with **all** of the above criteria |
+
+If you do not see the success icon in your Compliance dashboard; please review the above criteria for the Merge Requests
+project to make sure it complies with the separation of duties described above.