What theory or theories might apply to the following scenario ?

He was unemployed and receiving welfare, but J. Smith was somehow still living the high life, complete with a sports car, sailboat, and an expensive house in a luxury neighbourhood.

When authorities finally caught up with him, Smith was also in possession of three credits cards under other assumed identities.

Authorities believe he also was behind a comprehensive scheme that involved opening nearly 300 fraudulent bank accounts set up to establish credit lines in order to steal money from the institutions.

Investigators said Smith's operation accessed information of nearly 10,000 people, about 400 of whom had their identities stolen for the purpose of obtaining credit cards. Commercial mailboxes were opened under the false or stolen identities, which were then used to secure credit cards on individual accounts.

The result of Smith's fraud has been significant. His identity theft victims are still trying to reclaim their credit standings and their identities. Banks also incurred losses of up to 1,300,000 US.