Ladies and Gents, the Leader of the "Free" World.
US leader crashed by trying to 'pedal, wave and speak at same time'.
The official police incident report states: "[The unit] was requested to cover the road junction on the Auchterarder to Braco Road as the President of the USA, George Bush, was cycling through." The report goes on: "[At] about 1800 hours the President approached the junction at speed on the bicycle. The road was damp at the time. As the President passed the junction at speed he raised his left arm from the handlebars to wave to the police officers present while shouting 'thanks, you guys, for coming'.
"As he did this he lost control of the cycle, falling to the ground, causing both himself and his bicycle to strike [the officer] on the lower legs. [The officer] fell to the ground, striking his head. The President continued along the ground for approximately five metres, causing himself a number of abrasions. The officers... then assisted both injured parties."
Thanks to Litz over at Eschaton for this.