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                                                                    EXHIBIT 8.2

                       TESTA, HURWITZ & THIBEAULT, LLP
                     HIGH STREET TOWER, 125 HIGH STREET
                         BOSTON, MASSACHUSETTS 02110



                                                            July 18, 1996



Cadre Technologies Inc.
222 Richmond Street
Providence, RI 02903

Ladies and Gentlemen:

      This opinion is being delivered to you for the purpose of satisfying a
condition set forth in Section 7.1.7 of the Agreement and Plan of Merger dated
March 25, 1996, by and among Bachman Information Systems, Inc., a Massachusetts
corporation ("Bachman"), B.C. Acquisition Corp., a Delaware corporation and
wholly-owned subsidiary of Bachman ("Merger Sub"), and Cadre Technologies Inc.,
a Delaware corporation ("Cadre") (the "Merger Agreement"). Pursuant to the
Merger Agreement, Merger Sub will merge with and into Cadre (the "Merger"), and
Cadre will become a wholly-owned subsidiary of Bachman.

      We have acted as legal counsel to Cadre in connection with the Merger. As
such, and for the purpose of rendering this opinion, we have examined and are
relying upon (without any independent investigation or review thereof) the truth
and accuracy, at all relevant times, of the statements, covenants,
representations and warranties contained in the following documents:
              
      1.    The Merger Agreement (including Exhibits);

      2.    Representations made to us by Bachman and Merger Sub;

      3.    Representations made to us by Cadre;

      4.    The Bachman Affiliate Agreements;

      5.    The Cadre Affiliate Agreements;

      6.    The Prospectus/Joint Proxy Statement filed by Bachman with a
            Registration Statement on Form S-4 with the Securities and Exchange
            Commission pursuant to the Securities Act of 1933 (the "Registration
            Statement"); and



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      7.    Such other instruments and documents related to the formation,
            organization and operation of Bachman, Cadre and Merger Sub or to
            the consummation of the Merger and the transactions contemplated
            thereby as we have deemed necessary or appropriate.

      Except as otherwise provided, capitalized terms referred to herein have
the meanings set forth in the Merger Agreement or the Registration Statement.
All section references, unless otherwise indicated, are to the Internal Revenue
Code of 1986, as amended (the "Code"). In connection with rendering this
opinion, we have assumed or obtained representations (and are relying thereon,
without any independent investigation or review thereof) to the effect that:

      1. Original documents (including signatures) are authentic, documents
submitted to us as copies conform to the original documents, and there has been
due execution and delivery of all documents where due execution and delivery are
prerequisites to effectiveness thereof.

      2. The Merger will be effective under the applicable state law.

      3. The continuity of interest requirement as specified in Treas. Reg. 
[Section] 1.368-1(b) and as interpreted by certain Internal Revenue Service 
rulings and federal judicial decisions will be satisfied.

      4. All conditions to the closing of the Merger have been satisfied.

      Based on our examination of the foregoing items and subject to the
assumptions, exceptions, limitations and qualifications set forth herein, we are
of the opinion that:

      1. The Merger will constitute a "reorganization" within the meaning of
Section 368(a) of the Code, with each of Bachman, Merger Sub, and Cadre
qualifying as a "party to the reorganization" under Section 368(b) of the Code.

      2. No gain or loss will be recognized by holders of Cadre Common Stock
upon their receipt in the Merger of Bachman Common Stock solely in exchange for
Cadre Common Stock.

      3. The aggregate tax basis of the Bachman Common Stock received in the
Merger will be the same as the aggregate tax basis of Cadre Common Stock
surrendered in exchange therefor.


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      4. The holding period of the Bachman Common Stock received in the Merger
will include the period for which the Cadre Common Stock surrendered in exchange
therefor was held, provided that the Cadre Common Stock is held as a capital
asset at the time of the Merger.

      5. A stockholder who exercises dissenters' rights with respect to a share
of Cadre Common Stock and receives payment for such share in cash will generally
recognize gain or loss, for federal income tax purposes, measured by the
difference between the holder's basis in such share and the amount of cash
received, provided that the payment is neither essentially equivalent to a
dividend within the meaning of Section 302 of the Code nor has the effect of a
distribution of a dividend within the meaning of Section 356(a)(2) of the Code
(collectively, a "Dividend Equivalent Transaction"). Such gain or loss generally
will be capital gain or loss, provided that the Cadre Common Stock is held as a
capital asset at the time of the Merger, and will be long-term capital gain or
loss if the Cadre Common Stock has been held for more than one year at the time
of the Merger. A sale of Cadre Common Stock pursuant to an exercise of
dissenters' rights will generally not be a Dividend Equivalent Transaction if,
as a result of such exercise, the stockholder exercising dissenters' rights owns
no shares of Bachman Common Stock (either actually or constructively within the
meaning of Section 318 of the Code). If, however, a stockholder's sale for cash
of Cadre Common Stock pursuant to an exercise of dissenters' rights is a
Dividend Equivalent Transaction, then such stockholder may recognize income for
federal income tax purposes in an amount up to the entire amount of cash so
received.

      6.    Cadre will not recognize material amounts of gain or loss solely as
a result of the Merger.

      In addition to the assumptions set forth above, this opinion is subject to
the exceptions, limitations and qualifications set forth below.

      1. This opinion represents and is based upon our best judgment regarding
the application of United States federal income tax laws arising under the Code,
existing judicial decisions, administrative regulations and published rulings
and procedures. Our opinion is not binding upon the Internal Revenue Service or
the courts, and the Internal Revenue Service is not precluded from successfully
asserting a contrary position. Furthermore, no assurance can be given that
future legislative, judicial or administrative changes, on either a prospective
or retroactive basis, would not adversely affect the accuracy of the conclusions
stated herein. Nevertheless, we undertake no responsibility to advise you of any
new developments in the application or interpretation of the federal income tax
laws.

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      2. This opinion addresses only the specific tax issues set forth above,
and does not address any other federal, state, local or foreign tax consequences
that may result from the Merger or any other transaction (including any
transaction undertaken in connection with the Merger). In particular, we express
no opinion regarding (i) whether and the extent to which any holder of Cadre
Common Stock who has provided or will provide services to Cadre, Bachman or
Merger Sub will have compensation income under any provision of the Code; (ii)
the effects of such compensation income, including but not limited to the effect
upon the basis and holding period of the Bachman Common Stock received by any
such holder in the Merger; (iii) the potential application of the "golden
parachute" provisions of the Code (Sections 280G, 3121(v)(2) and 4999), the
alternative minimum tax provisions of the Code (Sections 55, 56 and 57) or
Sections 108, 305, 306, 357, 424 and 708 of the Code, or the regulations
promulgated thereunder; (iv) other than as specifically set forth in this
opinion, or the regulations promulgated thereunder; (iv) other than as
specifically set forth in this opinion, the tax consequences of the Merger to
Bachman, Merger Sub or Cadre, including without limitation the recognition of
any gain and the survival and/or availability, after the Merger, of any of the
federal income tax attributes or elections of Cadre, after application of any
provision of the Code, any regulations promulgated thereunder and any judicial
interpretations thereof; (v) the basis of any equity interest in Cadre acquired
by Bachman in the Merger; (vi) the tax consequences of any transaction in which
Cadre Common Stock or a right to acquire such stock was received; and (vii) the
tax consequences of the Merger (including the opinion set forth above) as
applied to specific stockholders of Cadre and/or holders of options or warrants
for Cadre Common Stock in light of their particular circumstances, including but
limited to dealers in securities, corporate shareholders subject to the
alternative minimum tax, foreign persons, and holders of shares acquired upon
exercise of stock options or in other compensatory transactions including,
without limitation, the tax consequences to the holders of options and warrants
for Cadre Common Stock of Bachman's assumption of outstanding options and
warrants for Cadre Common Stock.

      3. No opinion is expressed as to any transaction other than the Merger as
described in the Merger Agreement (including, without limitation, the Cadre Loan
or guarantee thereof, the Cadmount Agreement and escrow, or the acquisition by
Cadre of Westmount Technology B.V.) or to any transaction whatsoever, including
the Merger, if all the transactions described in the Merger Agreement are not
consummated in accordance with the terms of the Merger Agreement and without
waiver or breach of any material provision thereof or if all of the
representations, warranties, statements and assumptions upon which we relied are
not true and accurate at all relevant times. In the event any one of the
statements, representations, warranties, or assumptions upon which we have
relied to issue this opinion is incorrect, our opinion might be adversely
affected and may not be relied upon. We express no opinion concerning the
statements of law or legal conclusions contained in the discussion set forth in
the Registration Statement entitled "Carryforward of Net Operating Losses and
Tax Credits."


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      4. This opinion is intended solely for the purpose of satisfying a
condition set forth in Section 7.1.7 of the Merger Agreement; it may not be
relied upon for any other purpose or by any other person or entity, and may not
be made available to any other person or entity without our prior written
consent. We hereby consent to the inclusion of this opinion letter as an exhibit
to the Registration Statement.

                                    Very truly yours,

                                    /s/ Testa, Hurwitz & Thibeault, LLP

                                    TESTA, HURWITZ & THIBEAULT, LLP


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