He incurred great unpopularity by his abuse of lettres de cachet, and had to resign in 1775.
But neither Necker nor his wife cared to remain out of office, and in 1787 Necker was banished by "lettre de cachet" 40 leagues from Paris for attacking Calonne.
It has been used to test the question whether Roman Catholic religious orders could enter India, and in 1870 an attempt was made thereby to challenge the validity of a warrant in the nature of a lettre de cachet issued by the viceroy (Ind.
After a period of work in Holland he betook himself to England, where his treatise on lettres de cachet had been much admired, being translated into English in 1787, and where he was soon admitted into the best Whig literary and political society of London, through his old schoolfellow Gilbert Elliot, who had now inherited his father's baronetcy and estates, and become a leading Whig member of parliament.
Protests against the lettres de cachet were made continually by the parlement of Paris and by the provincial parlements, and often also by the States-General.