In Mauritania , the last country to abolish slavery (in 1981),  it is estimated that up to 600,000 men, women and children, or 20% of the population, are enslaved with many used as bonded labour .    Slavery in Mauritania was criminalized in August 2007.  (although slavery as a practice was legally banned in 1981, it was not a crime to own a slave until 2007).  Although many slaves have escaped or have been freed since 2007, as of 2012 [update] , only one slave-owner had been sentenced to serve time in prison. 
A persuasive essay is a piece of writing that describes a particular perspective and provides evidence in support of that perspective. While similar to an argumentative essay, the logic of a persuasive essay can be based on emotion rather than substantiated evidence, and it does not need to take the counter argument into account. Whether you are writing an essay for a composition class, or you are sending a letter to a newspaper editor, having a carefully crafted argument with solid evidence will make your writing more convincing and effective.