If you are ever on a jury in a marijuana case, [you should] vote not guilty" - even if you think the defendant actually smoked pot, or sold it to another consenting adult. As a juror, you have this power under the Bill of Rights; if you exercise it, you become part of a proud tradition of American jurors who helped make our laws fairer. [This] information ... about a constitutional doctrine called "jury nullification" is absolutely true. But if federal prosecutors in New York get their way, telling the truth to potential jurors could result in a six-month prison sentence. Earlier this year, prosecutors charged Julian P. Heicklen, a retired chemistry professor, with jury tampering because he stood outside the federal courthouse in Manhattan providing information about jury nullification to passers-by. The prosecutors in this case are wrong. The First Amendment exists to protect speech like this - honest information that the government prefers citizens not know. Laws against jury tampering are intended to deter people from threatening or intimidating jurors. To contort these laws to justify punishing Mr. Heicklen, [is] unconstitutional. Jury nullification is not new; its proponents have included John Hancock and John Adams. The doctrine is premised on the idea that ordinary citizens, not government officials, should have the final say as to whether a person should be punished. As Adams put it, it is each juror's "duty" to vote based on his or her "own best understanding, judgment and conscience, though in direct opposition to the direction of the court."