ne injuste vexes (nee in-j<<schwa>>s-tee vek-seez), n.[Law Latin “do not trouble unjustly”] Hist. A writ prohibiting a lord from demanding more services from a tenant than the tenure allowed.

“The writ of ne injuste vexes… which prohibits distresses for greater services than are really due to the lord; being itself of the prohibitory kind, and yet in the nature of a writ of right. It lies, where the tenant in fee-simple and his ancestors have held of the lord by certain services; and the lord hath obtained seisin of more or greater services, by the inadvertent payment or performance of them by the tenant himself. Here the tenant cannot … avoid the lord’s possessory right, because of the seisin given by his own hands; but is driven to this writ, to devest the lord’s possession, and establish the mere right of property, by ascertaining the services, and reducing them to their proper standard.” 3 William Blackstone, Commentaries on the Laws of England 234 (1768).

[Blacks Law 8th]