Dennis @ PerfectForms
You really only need to control the state (normal/hidden/read only/disabled) of your submit buttons in the form. That way even if edits are made, they cannot be submitted. You could also make entire pages read only. You can determine the state of an object (or page)based on the role and stage (who is viewing it and when). See our documentation for an Overview of field state scenarios: http://www.perfectforms.com/Documentation/manual/html/?fa_setting_field_state_scenarios.htm.
Since users must log in to view reports, you could also capture their user name and change the state of objects based on the user. If you want to get more involved you can allow edits but record the user name and show a message like: “Rooman, your edits will be made permanent, and your changes recorded are you certain you want to submit?”