15 USC 1692 - Congressional findings and declaration of purpose

(a) Abusive practices 
There is abundant evidence of the use of abusive, deceptive, and unfair debt collection practices by many debt collectors. Abusive debt collection practices contribute to the number of personal bankruptcies, to marital instability, to the loss of jobs, and to invasions of individual privacy.
(b) Inadequacy of laws 
Existing laws and procedures for redressing these injuries are inadequate to protect consumers.
(c) Available non-abusive collection methods 
Means other than misrepresentation or other abusive debt collection practices are available for the effective collection of debts.
(d) Interstate commerce 
Abusive debt collection practices are carried on to a substantial extent in interstate commerce and through means and instrumentalities of such commerce. Even where abusive debt collection practices are purely intrastate in character, they nevertheless directly affect interstate commerce.
(e) Purposes 
It is the purpose of this subchapter to eliminate abusive debt collection practices by debt collectors, to insure that those debt collectors who refrain from using abusive debt collection practices are not competitively disadvantaged, and to promote consistent State action to protect consumers against debt collection abuses.