The European equivalent normally prints up a credit-card-sized card which contains this type of information:

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You have the right to speak to a lawyer during your detention, and to have one present during any interview. We recommend:
(name of recommended law company): (phone number of lawyer)
You also have the right to have someone informed of your arrest.
If you have been arrested, or witnessed an arrest and need support contact:
(legal observer group's name, email and phone number)

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This can normally be given to people during an arrest. The lawyer or law firm, of course, is one that specialises in this, and is ready to be phoned.

In the case of people worried about being arrested, it's an idea to sew the name and number of such a lawyer inside their clothing.

One of the main purposes of such observers is to keep things relaxed and friendly - people can be terrified about what's going to happen to them, or their kids if they're in school or creche, etc; this kind of terror can be infectious and can make officials behave as they shouldn't.