The grounds for this is that he has chosen to ignore prior precedent from US. V. Miller in his DC v. Heller decision. Scalia was bound by precedent which he chose to ignore.
Perhaps the Court’s approach to the text is acceptable advocacy, but it is surely an unusual approach for judges to follow.
Justice Steven is polite, but I will use these terms since they are legal terms.
ignorance XIII. — (O)F. — L. ignōrantia, f. prp. of ignōrāre not to know, misunderstand, disregard, rel. to ignārus unaware; see -ANCE.
So ignorant XIV. ignore †not to know XVII; (of a grand jury) reject (a bill); refuse to take notice of XIX. — (O)F. ignorer or L. ignōrāre.
Ignorantia juris non excusat.
This is especially true for someone who purports to be a high court judge.
And I hope he bloody sues me because I want to hear his explanation as to why he ignored this:
In the absence of any evidence tending to show that possession or use of a 'shotgun having a barrel of less than eighteen inches in length' at this time has some reasonable relationship to the preservation or efficiency of a well regulated militia, we cannot say that the Second Amendment guarantees the right to keep and bear such an instrument. Certainly it is not within judicial notice that this weapon is any part of the ordinary military equipment or that its use could contribute to the common defense. Aymette v. State of Tennessee, 2 Humph., Tenn., 154, 158.
The Constitution as originally adopted granted to the Congress power- 'To provide for calling forth the Militia to execute the Laws of the Union, suppress Insurrections and repel Invasions; To provide for organizing, arming, and disciplining, the Militia, and for governing such Part of them as may be employed in the Service of the United States, reserving to the States respectively, the Appointment of the Officers, and the Authority of training the Militia according to the discipline prescribed by Congress.' U.S.C.A.Const. art. 1, 8. With obvious purpose to assure the continuation and render possible the effectiveness of such forces the declaration and guarantee of the Second Amendment were made. It must be interpreted and applied with that end in view.
UNITED STATES v. MILLER, 307 U.S. 174 (1939)