Exhibit 5.1
CONSENT OF INDEPENDENT ACCOUNTANTS
The Sponsors and Trustee of
Municipal Investment Trust Fund--Insured Series--401, Defined Asset Funds
We consent to the use in this Post-Effective Amendment No. 2 to Registration
Statement No. 333-65309 of our opinion dated December 7, 2000 appearing in the
Prospectus, which is part of such Registration Statement, and to the reference
to us under the heading "How The Fund Works--Auditors" in such Prospectus.
DELOITTE & TOUCHE LLP
New York, N.Y.
January 17, 2001
