The Importance of an Independent Judicial Power to oppose excesses of legislatures or parliaments as the anti-immigrant laws that we are watching lately in Arizona and Georgia :
Montesquieu and the Theory of Separation of Powers :
Montesquieu in Wikipedia
Some excerpts :
Charles de Secondat, baron de Montesquieu (1689–1755) was a French social commentator and political philosopher. His theories deeply influenced the American Founders, especially his belief that the state powers should be separated into legislative, executive, and judicial branches, which formed the basis for separation of powers under the United States Constitution.
After having studied at the Catholic College of Juilly, Charles-Louis de Secondat married. His wife, Jeanne de Lartigue, a Protestant, brought him a substantial dowry when he was 26. The next year, he inherited a fortune upon the death of his uncle, as well as the title Baron de Montesquieu and Président à Mortier in the Parliament of Bordeaux. By that time, England had declared itself a constitutional monarchy in the wake of its Glorious Revolution (1688–89), and had joined with Scotland in the Union of 1707 to form the Kingdom of Great Britain. In 1715 the long-reigning Louis XIV died and was succeeded by the five-year-old Louis XV. These national transformations impacted Montesquieu greatly; he would later refer to them repeatedly in his work.
Soon afterwards, he achieved literary success with the publication of his Lettres persanes (Persian Letters, 1721), a satire based on the imaginary correspondence of a Persian visitor to Paris, pointing out the absurdities of contemporary society. He next published Considérations sur les causes de la grandeur des Romains et de leur décadence (Considerations on the Causes of the Grandeur and Decadence of the Romans, 1734), considered by some scholars a transition from The Persian Letters to his master work. De l'Esprit des Lois (The Spirit of the Laws) was originally published anonymously in 1748 and quickly rose to a position of enormous influence. In France, it met with an unfriendly reception from both supporters and opponents of the regime. The Catholic Church banned l'Esprit – along with many of Montesquieu's other works – in 1751 and included it on the Index of Prohibited Books. It received the highest praise from the rest of Europe, especially Britain.
Montesquieu was also highly regarded in the British colonies in America as a champion of British liberty (though not of American independence). Political scientist Donald Lutz found that Montesquieu was the most frequently quoted authority on government and politics in colonial pre-revolutionary British America, cited more by the American founders than any source except for the Bible. Following the American secession, Montesquieu's work remained a powerful influence on many of the American founders, most notably James Madison of Virginia, the "Father of the Constitution". Montesquieu's philosophy that "government should be set up so that no man need be afraid of another" reminded Madison and others that a free and stable foundation for their new national government required a clearly defined and balanced separation of powers.
Besides composing additional works on society and politics, Montesquieu traveled for a number of years through Europe including Austria and Hungary, spending a year in Italy and 18 months in England before resettling in France. He was troubled by poor eyesight, and was completely blind by the time he died from a high fever in 1755. He was buried in the Église Saint-Sulpice, Paris.