Dethmers, C. J.

In these consolidated cases plaintiff sues respective defendants to recover personal property taxes paid under protest. It was engaged in the business of warehousing, wholesaling and distributing steel tubing in Detroit in connection with which it had on hand a quantity of “inventory” subject to personal property tax. Plaintiff’s declarations allege that its “inventory” and those of other taxpayers were assessed at true cash value; that this was discriminatory in that real estate in Detroit was at the same time assessed at substantially less than true cash value with the result that plaintiff and other owners of “inventories” were required to pay more than their fair share' of the taxes; that the discrimination was deliberate, intentional, systematic, arbitrary, calculated and fraudulent, with the intention and for the purpose of requiring the owners of “inventories” to pay taxes thereon on-a higher *386 basis than that on which taxes on real estate were paid; that this operated to deny plaintiff equal protection of the laws and deprive it of property without due process of law.

The cases reached the pretrial admission and discovery docket. The circuit judge entered an order granting plaintiff the right of discovery and to subpoena for examination certain city officials, including members of the board of assessors, and certain of their books, papers and documents.

Defendant city filed a motion to suppress the subpoenas duces tecum on the ground that the testimony, records, books and papers sought were privileged, except for the assessment rolls, published reports and communications, and other records usually open to public inspection. This claim of privilege is urged particularly with respect to what .defendant city styles (1) nonpublic documents, such as office work papers, notes, statements of staff members and of assessors, records of property sales, construction cost studies, miscellaneous work data with information and notations, et cetera, and (2) limited-public records available only to the taxpayers to whose property the same relate, such as personal property statements, land calculation cards, building construction sheets, et cetera. Defendants predicate .this claim of privilege on the custom, usage and classification of the records by the board of assessors. From an order denying the motion to.suppress, defendants have appealed, on leave granted.

We are cited to no authority for the proposition that the records and papers which' defendants call nonpublic or limited-public are privileged as such either because of the long-standing practice and custom of the office of the board of assessors in treating them thus or because they are not public records required by law to be kept by defendant city or its officers. In litigation between private parties papers *387 may be possessed which are not public, but their private status does not necessarily render them privileged from examination by the opposite party under proper court order. The rule of evidence is the same whether defendant be a person or a municipal corporation. 81 CJS, States, § 215. Obviously, the public or private character of the papers is not, of itself, controlling of the question of privilege.

Defendants rely largely on Chicago, Burlington & Quincy R. Co. v. Babcock, 204 US 585 (27 S Ct 326, 51 L ed 636), Michigan cases citing it, i.e., Newport Mining Co. v. City of Ironwood, 185 Mich 668; Copper Range Co. v. Adams Township, 208 Mich 209; Lowrie & Robinson Lumber Co. v. City of Detroit, 237 Mich 138; Twenty-Two Charlotte, Inc., v. City of Detroit, 294 Mich 275, and the rule announced in Babcoclc that in an action attacking the validity of an assessment and tax the assessing officers may not be subjected to “cross-examination with regard to the operation of their minds in valuing and taxing” property. We agree with plaintiff that such holding is not authority for defendants’, position that the only records the assessors are required to produce are public records or those which they have by custom, usage and practice classified as public or that the only testimony they may be required to give is' limited to identification of such “public” records. While cross-examination may not be directed to the operation of the assessors’ minds in making the assessments, to the weight they gave various items of information, nor to their reasons for assessing different properties in varying amounts, they may be questioned concerning the information and materials at their disposal, used by them in making the assessments. See cases cited in Babcoclc.

Under the previous decisions of this Court, we-cannot agree with plaintiff’s position, urged on cross appeal, that the allegations in its declarations con *388 stituting what it conceives tó he charges of fraud (but see. Naph-Sol Refining Co. v. Muskegon Township, 346 Mich 16), take these cases outside the rule in Babcock which prohibits cross-examination of assessing officers with regard to the operation of their minds in making the assessments.

Consideration of other questions raised we do not deem necessary to decision herein.

Affirmed, without costs, neither party having prevailed in full.

Sharpe, Smith, Boyles, Kelly, Carr, and Black, JJ., concurred. • Edwards, J., took no part in the decision of this case.