On April 14th, 1736, Andrew Wilson was found guilty of smuggling and sentenced to death in Edinburgh
, much to the outrage of the Edinburgh citizens, who were sympathetic toward him, on account of him having sacrificed himself in order to allow his accomplice George Robertson escape during their final church service
, when he held off the guards. This meant that on the day of his execution, instead of the usual high spirits there was tension in the air. Expecting disturbances from the crowd, the town council had ordered additional soldiers to be brought down from Edinburgh Castle
into town where the execution was to take place, something which infuriated Captain John Porteous of the City Watch, who saw this as an attempt to undermine his authority and as a result was in an angry mood on the day and also, according to some witnesses, under the influence of alcohol.
The crowd stood in silence as Wilson was hanged, and as his body was taken down, some members of the crowd began to pelt members of the watch who stood guard on the scaffold with stones and pieces of clay. Porteous ordered his men to fire into the crowd. When they hesitated, he gave the order again. This time they did as he commanded, discharging their muskets into the crowd. Many of the guards, who knew many of the people they were ordered to shoot, instead fired over the heads of the 'rioters', however this only meant that the bullets hit the on-lookers who had been watching the execution from their windows, one of whom, a young boy, was killed. The crowd, who by now had suffered nine fatalities, turned and fled down the West-Bow, where they were cut off by Porteous who again ordered his men to fire, which they did. A full-scale riot ensued, lasting for up to a week.
Porteous, along with thirty of his men, was arrested and charged with 'firing into the crowd without any just cause or provocation'. He was found guilty by just one vote, and sentenced to hang, however the residing monarch, Queen Caroline, allowed for six weeks reprieve. However, on the evening of the original date set for his hanging, a well thought-out plan was put into effect. A small number of citizens seized the cities gate house, preventing the watch from entering the town from the Cannongate. Once they had done this, another small band of civilians made their way to the Tolbooth Prison, where Porteous was being held. Here, they burned down the door and overpowered the guards. They seized Porteous and dragged him to the Grassmarket, where he was hanged from a washing line. Though some versions of the story say that the crowd stood in an eerie silence as he hanged, it is far more likely that his body was taken down and hacked with axes and swords several times before he eventually died.