Very interesting. I'm not sure if the Spanish or Italians would be pleased with the detective's comments. But the point he made about traffic offenses. I disagree with VWE, honesty is not a good policy when it comes to police stops. Courtesy is a good policy. I was stopped on my bike once by the police. He told me I was doing 95. I said 'No way'. 'Well what speed were you doing? Expecting me to be dumb enough to say 'only 85 or something'. In any case I wasn't lying. I had no idea what speed I was doing as the speedo cable broke long before.

Over the years I took the same attitude, courtesy and little talking. I have never had a single driving conviction in 24 years of outright hooliganism.

(I'm not that proud of it though).
In this country, you definitely do have the right to remain silent. Many criminals take advantage of it. I can think of two wife killers who definitley did it but got away with it by saying nothing. Worse still, well known gangsters and terrorists simply say nothing during interviews. Even their low level followers keep their mouths shut because all interviews are taped, with a copy given to the accused. If they are released, their boss, listens to the tape. Needless to say, any indiscretion is dealt with by a bullet or two to the head. Of course when the boss is brought in. He says nothing except maybe 'I'm taking the fifh' which doesn't apply here, but everyone has seen the movies.
But the point is fair, guilty or innocent, say nothing.
Here's a clip from the Movie 'Ordinary decent criminal' Kevin Spacey played a real gangster. Note how he says nothing. Note also his alibi when the Police golf course was ripped apart. In the end the man he played was never convicted of anything despite being followed day and night by the cops. He was finally assassinated by the IRA because he crossed them too and they had a subtly different justice system.
http://www.youtube.com/watch?v=91wGPQe3-HM