Hell, on top of that, encrypt two volumes with two different crimes. One volume with a lesser crime (jaywalking), containing a video of you jaywalking and a text explanation as a "proof of concept". That way you can divulge that key to decrypt that volume and show you're not just bullshitting. Then, a second more serious crime confession to encrypt the second volume with the real data. The first will show that you have encrypted drives with confessions, to give weight to the argument that divulging the second drive's key would be self-incrimination.