Smart, sensible establishment figure are starting to fear that the executive branch will not submit to its own arrest because the President controls the police force. They are game-planning how the legislative branch might have to serve as its own constabulatory [1].
We're getting into "how many divisions does the Pope have" territory here.
Links:
[1] http://www.washingtonpost.com/wp-dyn/content/article/2007/07/20/AR2007072001802.html