Mistake of law constitutes a mistake, within the meaning of this part, only when it arises from:

1. (1) a misapprehension of the law by all parties, all supposing that they knew and understood it and all making substantially the same mistake as to the law; or
2. (2) a misapprehension of the law by one party of which the others are aware at the time of contracting but which they do not rectify.

History: En. Sec. 2123, Civ. C. 1895; re-en. Sec. 4984, Rev. C. 1907; re-en. Sec. 7486, R.C.M. 1921; Cal. Civ. C. Sec. 1578; Field Civ. C. Sec. 763; re-en. Sec. 7486, R.C.M. 1935; R.C.M. 1947, 13-314.