Black's Law Dictionary (2nd edition)dictionaries

Shall

As used in statutes and similar Instruments, this word is generally im-perative or mandatory; but it may be con-strued as merely permissive or directory, (as equivalent to “may,”) to carry ont the legislative intention and in cases where no right or benefit to any one depends on its being taken iu the imperative sense, and where no public or private right is impaired by its interpretation in the other sense. Also, as against the government, “shall" is to be construed as “may,” unless a contrary intention is manifest. See wheeler v. Chl-cago, 24 111. 105, 76 Am. Dec. 736; People v. Chicago Sanitary Dist., 184 111. 597, 56 N. E. 953; Madison v. Daley (C. C.) 58 Fed. 753 ; Cairo & F. R. Co. v. Hecht, 95 U. S. 170, 24 L. Ed. 423

Source: Black's Law Dictionary 2nd Ed (1910)