Section 806 of the Fair Debt Collection Practices Act (FDCPA).
The Fair Debt Collection Practices Act - Section 806
806. Harassment or abuse [15 USC 1692d]
A debt collector may not engage in any conduct the natural consequence of which
is to harass, oppress, or abuse any person in connection with the collection of
a debt. Without limiting the general application of the foregoing, the following
conduct is a violation of this section:
(1) The use or threat of use of violence or other criminal means to harm the
physical person, reputation, or property of any person.
(2) The use of obscene or profane language or language the natural consequence
of which is to abuse the hearer or reader.
(3) The publication of a list of consumers who allegedly refuse to pay debts,
except to a consumer reporting agency or to persons meeting the requirements of
section 603(f) or 604(3)1 of this Act.
(4) The advertisement for sale of any debt to coerce payment of the debt.
(5) Causing a telephone to ring or engaging any person in telephone conversation
repeatedly or continuously with intent to annoy, abuse, or harass any person at
the called number.
(6) Except as provided in section 804, the placement of telephone calls without
meaningful disclosure of the caller's identity.