after debate of whether he should be charged with assault (max 15 years) or just insult of foreign leader (max 3 years), they went with the second one. he got the maximum of 3 years which was later reduced to one and he was released for good behaviour after 9 months. he complained about being tortured while in the prison.

He was released on 15 September 2009, claiming that he had been systematically tortured during his time in jail and one of his front teeth was seen missing. Al-Zaidi said that he had been beaten with electric cables and iron bars and immersed in cold water. On 19 October 2009, while in Switzerland where he expected to have medical treatment for his injuries, he stated, "I suffered a great deal. I still have problems with my teeth, back and other parts of my body where I was tortured.

https://en.wikipedia.org/wiki/George_W._Bush_shoe-throwing_incident#Trial_and_sentence