Actually there is. When you exercise your right to remain silent, the cops apparently have to stop asking you questions -- it says as much in the linked article. (Presumably to avoid any appearance of attempting to force or intimidate the suspect.) The ruling essentially says the cops are not obligated to regard complete silence as exercising your right to remain silent.
-- Bob
---------
Then the horns kicked in...
...and my shoes began to squeak.
-- Bob
---------
Then the horns kicked in...
...and my shoes began to squeak.