The people who hated the Queen held it up as an example of the unnatural policies she would foist on them if given free rein.
Usually this metaphor is not used with royalty as anecedant. In this particular case, "reign" is more appropreate in context.
... the unnatural policies she would foist on them if given free "reign".
Okay, you've got a point, as long as the " " stay visible.