Cases that breach their resolution SLA should be assigned a Case Breach Reason.

These can be defined in Settings - Case Breach Reasons.

Here you can add, edit and delete reasons.

Reasons can only be deleted if they are not currently in use. You can use the All Cases report to find cases that have that status assigned.

The reason can be seen on a breached case record:

Breach Description is a free-typed, optional field.