No, legally they cannot. The Fair Debt Collection Practices Act contains information as to what a collection agency can and cannot do, what times they can call you, etc. You may obtain a copy of the Fair Debt Collection Practices Act from the Federal Trade Commission, or you can learn all about it in our ebook/CD "Credit Repair 101: An Educational Guide to Repairing and Rebuilding Your Credit" which also includes the form letters you will need to stop the harassment.