I was thinking that vocalizing a password could fall under the "right to remain silent."

The Fifth Amendment:
"No person shall be held to answer for a capital, or otherwise infamous crime, unless on a presentment or indictment of a grand jury, except in cases arising in the land or naval forces, or in the militia, when in actual service in time of war or public danger; nor shall any person be subject for the same offense to be twice put in jeopardy of life or limb; nor shall be compelled in any criminal case to be a witness against himself , nor be deprived of life, liberty, or property, without due process of law; nor shall private property be taken for public use, without just compensation."

If one can be legally forced to disclose a password, the same could be imposed to decrypt data...

I hope someone can come up with actual legal cites for this matter...