You have to speak up if you want to remain silent.

Says the Supreme Court: Ve haf vays to make you talk!!  

There is a real pearl in this.  That if you state clearly that you invoke your right to council before questioning and that you do not choose to make a statement at this time...  the Police run grave risks in continuing badgering or questioning the detainee.  

I believe that it would be much easier to make this happen by turning the tables early with "Am I free to go?"  If not, then "I want coucil" would be the next thing I say.

Overkill?  Perhaps.  But better safe than sorry.
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to never just remain silent, but recite one sentence: "I would like to speak with an attorney, and will answer no questions unless my attorney is present."

Actually, that's not *quite* true.  In many states, you are required to identify yourself and provide your address if you're arrested or detained.  And, providing that information doesn't affect your right to remain silent.  What was recommended to me by a civil rights/criminal attorney was:

"My name is ____.  I live at _______.  I have not committed any crime and respectfully decline to answer any and all questions without my attorney present.   If you have evidence that I have committed a crime, then I demand that you charge me immediately and allow me to call my attorney.  If I am not under arrest, then may I please leave?"

It covers all your bases: you identify yourself, you declare that you won't answer questions, that you want an attorney, or to leave if they are not charging you.

that you have not committed any crime.  The cop could say something back like:  "When did I say you committed a crime?  We just wanted to ask you a few questions.  What crime didn't you committ?"

You see how these things can get complicated?

You are correct that you must show ID and a residence (in most states anyways.) And after that, just STFU, and tell them you want to STFU also.

You are mistaken.

According to the lawyer, you are making a general declaration of innocence and the police CANNOT use that against you.  And, since you clearly stated that you weren't going to answer any questions without an attorney, they can't ask you any more questions.  If they do, you simply repeat the statement.   It's not complicated at all.

is that STFU means STFU.  In the case the defendant actually spoke ... in response to continued questions from the police.  

The case really seems, as much as anything to set forth when the police must stop questioning you.  Rather than requiring an affirmative answer that you wish to continue speaking, it requires a verbal statement that you no longer wish to speak.

Not an attorney, so I'm not really up on when the police must stop questioning, but always assumed that it was as soon as you indicated that you wished it to stop.