investigatory practices

b. whenever practicable and appropriate, and not inconsistent with good investigatory practices such as canvassing a scene, interview complainants and witnesses at sites and times convenient for them, including at their residences or places of business;

in reference to:

"b. whenever practicable and appropriate, and not inconsistent with good investigatory practices such as canvassing a scene, interview complainants and witnesses at sites and times convenient for them, including at their residences or places of business;"
- Civil Rights Division Home Page (view on Google Sidewiki)