Errors, Misquotes, and Omissions in the Professional Historians McDonald Amicus Brief
As documented in the previous post, historical records directly link the Second Amendment and the 1780 Massachusetts Declaration of Rights provision indicating that the people have a right to keep and to bear arms. This post examines historical records linking British seizure of arms in Massachusetts to that state's declaration of rights arms provision, which is the only one of eight related period provisions specifying a right to "keep" arms.
The historians' McDonald brief misrepresents the Continental Congress' Declaration of the Causes and Necessity of Taking Up Arms, passed on July 6, 1775. Their completely misleading description of British "seizure of arms from Boston’s departing inhabitants", [p.37] an occurrence directly following the initiation of hostilities on April 19, 1775, misrepresents the incident. In return for the inhabitants, who were confined within the fortified town, depositing all of their arms with the town selectmen for safekeeping so they could be marked and returned to their owners at some future period, General Gage guaranteed the vast majority who wanted to depart that they could do so with all of their other possessions. The arms thus deposited by the inhabitants were seized by the British, and General Gage allowed only a small number of Bostonians to leave who desired to do so. Although this is the brief's sole mention of a specific British arms seizure, it is only part of the disarming activities carried on by the British in that colony. [The Founders View of the Rights to Bear Arms, pp.52-53]
Hostilities of the American Revolution began in Massachusetts when Major Pitcairn, leading advance British troops on their way to Concord to seize and destroy arms, attempted to disarm Americans on the green at Lexington. However, long before this disarming incident, which resulted in outright war, the British had been disarming Americans in Massachusetts by seizing gunpowder and arms for a considerable period of time. Almost seven months earlier, on September 1, 1774, Gage ordered out a secret military detail to seize the publicly owned powder in the Charlestown powder house and move it to a location under his military control. Due to false reports of casualties, this powder alarm as it was called resulted in tens of thousands of armed provincials marching toward Boston until the rumors were counteracted. General Gage ordered that no gunpowder, even that privately owned and stored in the Boston powder house, could be removed without his permission, which, unsurprisingly, could not be obtained. [FVRBA, pp.51, 36-38]
Period firearms were useless other than as clubs without gunpowder. Thus, seizure of powder was the equivalent of seizure of arms. General Gage started seizing all arms and ammunition being transported out through the land entrance of Boston after it was fortified. It was not until October 19, 1774 (with notification reaching the colonies much later) that the British halted importation of arms and ammunition into the colonies by law. The subsequent disarming of Bostonians by seizure of their arms after hostiles started in April of 1775 was intensified during July with a proclamation that anyone in Boston still found in possession of arms would be deemed an enemy of the king's government and punished. Mere possession of a firearm in one's home earned the violator of Gage's proclamation 75 days in prison. Thus, the people of Massachusetts, and especially the inhabitants of Boston, had been subjected to extensive seizure of arms by the British over a considerable period of time, from the beginning of September 1774 into April of 1775, and for Boston's inhabitants on until the British were actually driven out in 1776. [FVRBA, pp.36-39, 51-53, 57]
There was nothing even approaching the ongoing attempts to disarm the people of Massachusetts occurring in any of the other colonies. A case of arms stopped by customs officials in New York was much publicized, and the governor of Virginia seized some public powder and had it placed on a British vessel, resulting in Patrick Henry's march in May of 1775 to obtain possession or reimbursement. [FVRBA, p.53-54] But only in Massachusetts had there been ongoing and preplanned attempts to disarm the population for a long period of time extending from well prior to hostiles until they began, and in the case of the Bostonians, until well after.
In its attempts to tie the Second Amendment to English documents and ideas using American revolutionary era comments on self-preservation, the historians' brief completely ignores the eight revolutionary era American state bills of rights, every one of which contained a Second Amendment related progenitor. Four of these, including the very first, consisted of well regulated militia references understood as relating to an armed populace, while the other four used people have a right to bear arms language understood similarly. But only one state, the very last to adopt bear arms style language, specifically added the word "keep" in relation to arms in its Second Amendment predecessor. An attentive reader will not have to guess which state it was after viewing the more relevant American history connected to Second Amendment development presented in this and the previous post. It was Massachusetts, whose bill of rights arms provision the historians' were unable to accurately quote for some odd reason.
Recall that the historians' brief includes this claim:
"Historical records show that the Second Amendment was unrelated to any seizure of colonists’ arms by British troops." 
Based on the historical records discussed above and in the previous post, this assertion by the historians is not only erroneous but preposterous. Massachusetts' Declaration of Rights is the only one of eight equivalent state provisions, all of which contain Second Amendment predecessors, to specify that the people have a right to "keep" arms. That language is a direct result of the ongoing and extensive British actions seizing arms from the people of Massachusetts, and more particularly from the inhabitants of Boston, who were treated as nothing more than expendable hostages by the British after hostilities began.
The professional historians' McDonald brief supporting Chicago's gun control laws is completely unreliable historically and purposefully avoids discussion of the most relevant revolutionary era sources relating to the Second Amendment, the eight revolutionary era state bills of rights.