The whole purpose of the security clearance process is to try to predict future conduct based on past and current conduct. When a person has acted honestly and responsibly for a few years, it is much more indicative of their future conduct than something that happened further back in time. The challenge for most people is effectively explaining to an adjudicator - through their application form or a security interview - what has changed in their life that shows they will not get into the same unfavorable situation in the future. How should you explain your financial problems? (less info)