In court, you must assert your right to not testify against yourself.

Upon arrest, you're not obligated to speak or answer anything.

The police are not officers of the court, nor involved in court proceedings during their interactions with the public, so there is no expectation or explicit penalty for not answering. In court, while being questioned, you're compelled, under penalty of perjury, to testify in full and truthfully unless there is a reason you can or may not:

> Do you solemnly (swear/affirm) that you will tell the truth, the whole truth, and nothing but the truth?