After the Montejo v Louisiana ruling may police interrogate a suspect provided they waive their rights even when they know the suspect or defendant has been appointed counsel?

Answer 1

Montejo v. Louisana, 556 US ___ (2009)

The question is worded too broadly. This case was decided on a very narrow set of circumstances. In the final analysis, This particular defendant WAS convicted on a piece of evidence he voluntarily gave AFTER he had invoked his Miranda rights and AFTER he had been appointed a counsel.

The summary of the Supreme's decision finds that, although Montejo had already been Mirandized AND subsequently appointed counsel, neither he, nor the police, knew it at the time he wrote his self-incriminating letter. THAT, in point of fact, was the crux of the case. It's a well written decision that I believe still applies. In my experience, even though an arrestee has been Mirandized, AND appointed counsel, nothing bars the subject from making a voluntary statement (known as an "extemporaneous statement") which would tend to incriminate themselves, nor are the courts barred from hearing this extemporaneous uttering as evidence against them. You can Mirandize and appoint attorneys for defendants all day long, but there is no way you can legislate against a defendant blurting out remarks which turn out to be self-incriminating.

For a more detailed explanation of the case see below link: