The notion of security clearance and the way the department has handled it has been that it has been a security difficulty or problem or a security notion related to what type of work you're doing. So if you unfortunately have some issues at home and you do some bad things at home, that does not necessarily make you a security risk for being a truck driver. Therefore, not all criminal references in your background are necessarily going to determine if you get an assessment or a clearance or not.
On March 10th, 2009. See this statement in context.