Translate the following English sentence to French:
"Indeed, they must set in place the institutional conditions needed to launch a tangible and efficient cooperation process in the field of law - a process that must nevertheless cover all the stages needed to prevent the untimely impositions that are detrimental to legitimate national prescriptions in the field of justice, over which Member States have sovereign powers, and above all to prevent impositions that result in riding roughshod over basic civil rights."
Ce processus doit, néanmoins, franchir toutes les étapes nécessaires afin d'éviter des contraintes inopportunes au détriment des indications légitimes nationales en matière de justice, sur lesquelles les États membres sont souverains, et surtout afin d'éviter des contraintes qui finissent par fouler aux pieds les droits fondamentaux des citoyens.