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Exhibit 3.1
June 15, 2000
John Nuveen & Co. Incorporated
333 West Wacker Drive
Chicago, Illinois 60606
Re: Nuveen Unit Trusts, Series 90
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Gentlemen:
We have served as counsel for you, as Depositor of Nuveen Unit Trusts,
Series 90 (hereinafter referred to as the "Fund"), in connection with the
issuance under the Trust Indenture and Agreement dated the date hereof between
John Nuveen & Co. Incorporated, as Depositor, and The Chase Manhattan Bank, as
Trustee, of Units of fractional undivided interest in the one or more Trusts of
said Fund (hereinafter referred to as the "Units").
In connection therewith, we have examined such pertinent records and
documents and matters of law as we have deemed necessary in order to enable us
to express the opinions hereinafter set forth.
Based upon the foregoing, we are of the opinion that:
1. The execution and delivery of the Trust Indenture and Agreement and the
establishment of book entry positions and the execution and issuance of
certificates evidencing the Units in the Trust(s) of the Fund have been duly
authorized; and
2. The book entry positions and certificates evidencing the Units in the
Trust(s) of the Fund when duly established or duly executed and delivered by
the Depositor and the Trustee in accordance with the aforementioned Trust
Indenture and Agreement, will constitute valid and binding obligations of such
Trust(s) and the Depositor in accordance with the terms thereof.
We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement (File No. 333-34288) relating to the Units referred to
above and to the use of our name and to the reference to our firm in said
Registration Statement and in the related Prospectus.
Respectfully submitted,
/s/ Chapman and Cutler
Chapman and Cutler
