How Should You Scope an Internal Investigation?

Scope is the most consequential decision in an internal investigation, and it is usually made with very little to go by.

Draw the boundaries too tightly and the process looks overly managed in hindsight. Draw them too broadly and cost, timelines, and business disruption expand without necessarily improving the process or the outcome.

Part 3 of our Investigations series sets out how to approach scope.

How should you scope an internal investigation? 

A well-scoped investigation balances thoroughness with proportionality. The rationale should be principled, documented, and defensible. 

Start with Purpose 

Be clear about what the investigation is meant to accomplish. 

• Are the allegations substantiated? 
• Was law, policy, or professional obligation breached? 
• Findings only, or recommendations too? 

Purpose determines which questions the investigation must answer, and which it need not.  

Anchor in the Allegations 

Scope has to connect to what was alleged. But that connection requires judgment. 

• A narrow or generous reading of the allegations? 
• Should related complaints be folded in? 
• Who decides when the allegations are unclear? 

Set the Boundaries 

Translate purpose into parameters. 

• Issues: which questions will be investigated? 
• People: whose conduct and knowledge are relevant? 
• Time: how far back should this reach? 

Set the Reach 

• Entities: which business units, jurisdictions, or affiliates? 
• Evidence: which custodians, systems, and communications? 

 Every boundary needs a rational connection to the allegations and the risk. 

Calibrate to the Risk 

Not every allegation requires boiling the ocean. 

• How serious and credible are the allegations? 
• Could the conduct be systemic or ongoing? 
• What is the legal, regulatory, and reputational exposure? 

The goal is an investigation proportionate to the risk. 

The Bottom Line 

Scope should be revisited periodically. 

It should not expand through investigative drift. 

Want to learn more? 

Join us for Risk, Reputation and Response: Navigating Internal Investigations. 

• Monday, September 21, 2026 
• 12:00 p.m. to 1:30 p.m. ET 

Please contact clientevents@mccarthy.ca if you are interested in attending. 

Internal Investigations: Triggers, Scope, and Consequences Series

• Part 1: When Should you Conduct an Internal Investigation?
• Part 2: Key Considerations for In-House Counsel