We know very little about John Alexander, but what we know is provides some insight about the legal aspects of enlistment into the British army. He enlisted in the 4th (King's Own) Regiment of Foot, probably on 14 November 1777, in Philadelphia. It was unusual for men in America to enlist into regular British regiments during the war. Most who wished to join the army in America enlisted into the many Loyalist corps raised to augment the British army.
It's possible that Alexander was a deserter from the Continental army; a soldier named John Alexander went missing from the 5th Pennsylvania after the battle of Brandywine, but the name was common enough that we can't assume it is the same man. Several hundred men deserted from American service in the Philadelphia region in late 1777, discouraged by the string of defeats that Washington's army suffered. A substantial portion of those men are known to have enlisted into Loyalist regiments. It is entirely plausible that a few enlisted into regular British regiments, particularly if they were men with prior British army service. John Alexander may have been an escaped prisoner of war, a returned deserter, or even a veteran who had been discharged and wished to enlist again.
Whatever his background, Alexander was a British soldier from November 1777 until 4 March 1778 when he deserted. He took his spare clothing with him, but not his musket.
On 10 June, as the British were preparing to leave Philadelphia, a patrol of dragoons from the Queen's Rangers, one of the most storied Loyalist regiments, went out of Philadelphia to investigate a report that people coming in to the market from the countryside were being robbed by rebels. The dragoons scoured some woods were the rebels were reported to be hiding. One of them came upon a man "dressed in blue Coat & red Waistcoat with a Gold button and Loop to his hat, standing with a Woman," holding a musket with the butt resting on the ground. The dragoon was able to approach fairly close and challenge the man, brandishing his sword. The man claimed to be a member of the New Jersey militia, and the dragoon took him prisoner.
The militia man was put into the new jail in Philadelphia with other rebel prisoners, but was lodged in a dungeon with suspected deserters. He tried to escape by tunneling through the floor. It was his particular misfortune, however, that the jailer happened to be the former drum major of the 4th Regiment of Foot, who recognized Alexander and questioned him. Alexander initially denied his name and having met the former drum major, but when the jailor struck him with a cane Alexander admitted to both things. He was transferred to the old jail and held there with other deserters.
Preparing to march from Philadelphia to New York occupied the time of the army's administration, so Alexander was kept in confinement until the move to New York was completed; it is not known how the prisoner was conveyed. He went before a general court martial on 24 July in Brooklyn. A serjeant of the 4th Regiment testified to Alexander's enlistment, and deposed that he'd received pay and clothing from the regiment - in other words, that the army had fulfilled its obligations of the enlistment contract. An officer and a trooper of the Queen's Rangers described Alexander's capture.
Put on his defense, John Alexander gave an interesting argument. He claimed that he had not been properly enlisted and assumed himself to be only a volunteer, free to leave at any time he pleased. If he could prove this, he would have a valid case and could not be considered a deserter. He called upon a corporal in the 4th Regiment and the court questioned him:
Was Alexander ever attested as a soldier, that is, did a magistrate attest that he was legally enlisted? The corporal did not know. That worked in Alexander's favor.
Did the corporal have any doubt about the legality of Alexander's enlistment? "Not the least." Bad for Alexander.
"Did he ever hear the Prisoner say whilst he was with the 4th Regt. that he never had been attested?" "Yes he has frequently heard him say so." That was favorable for Alexander; he'd complained about not being attested, and the corporal knew it.
"Does he know of the Prisoner having ever heard the Articles of War read?" This was important, because the Articles of War spelled out the army's obligations to the soldier, and vice versa; hearing them read would mean that Alexander was aware of the laws governing enlistment and desertion. "Not the whole, but he had heard such as Circumstances would occasionally admit of." Not a clear answer. Apparently Alexander had heard only some of the Articles, those which pertained to specific events.
"Did the prisoner ever receive pay as a Soldier?" This was crucial. Alexander said that he'd never been paid, and therefore was under no obligation to the army. The corporal replied, "He received Pay from the Witness himself." Now things looked bad for Alexander.
"Does he know of the Prisoner having heard the 1st Article of War of the 6th Section read?" This Article was important for this particular case. It read,
The Penalty of Desertion: All Officers and Soldiers, who having received Pay, or having been duly inlisted in the Service, shall be convicted of having deserted the same, shall suffer death, or such other Punishment as by a Court-martial shall be inflicted.
Notice that is says "received pay" OR "inlisted", not AND. Although he denied it, Alexander had done one of these things, received pay. As for having heard the Article, the corporal said that Alexander "has heard it frequently & the Witness himself had told him that he must look upon himself as a Soldier in His Majesty’s Service, as much as if he had been attested before a Magistrate in England."
Things looked very bad for Alexander now, but he put his own question to the corporal, perhaps in the hope of convincing the court that his enlistment was not properly handled: "Did the Prisoner ever receive any Bounty or inlisting Money?" The corporal did not know abou that, but had told him that the enlistment bounty was Guinea and a half. This was similar to peacetime enlistment bounties in Great Britain, but less than typical bounties offered there in 1778. Maybe that's what Alexander's complaint was about; perhaps he'd heard from other recruits about higher bounties. The corporal also indicated that he'd given Alexander "about three quarters of a Dollar which he had at three different times."
Alexander told the court that he'd received only a Pistereen from the corporal, "and that having lent the Corporal money, he thought that that was given him part of Payment." He said that he did not intend to desert, but had gone for wood and was captured, put into jail, and consented to join the militia to escape confinement. He explained that he'd seen the Loyalist dragoons and hidden from his comrades so that he could surrender, and that after he was in captured he sent word to the 4th Regiment so that he could return to their service.
The court was not impressed by John Alexander's testimony, particularly in light of statements by a witness that he himself had called. He was found guilty, and sentenced to death.