The reason I would have to lie is that it is assumed that I am trying to make a statement about blacks being discriminated in the criminal justice system and that the case I will hear has to do with a black man being accused and that I would vote for acquittal no matter what because I think if others act as I do then the courts will revise their practices against blacks.
It could be acceptable to do this, but it would depend on certain assumptions being true.
Of course, utilitarianism says that when you are faced with two choices you should pick the one that will lead to the greatest total happiness for your society. It is okay to act in ways that might seem immoral if they will increase the total happiness of your society. In the case you present, you should lie if there will be a benefit to society that is greater than the harm you will cause. So, if you assume that African Americans will truly benefit from your actions, and if you assume that no one is actually hurt by them, you should lie to get on the jury.
I agree with Post 2, but the tradeoff might be the potential damage to the legal system caused by lying, and it could also be related to the specifics of the case. In other words, saying that you will vote for acquittal regardless of evidence makes the decision more complex from a utilitarian perspective. If the person is actually guilty of the crime, you have privileged one form of justice over another, which is not by any means anti-utilitarian, but it does make it very complex.
Depending on if you are talking about Act or Rule Utilitarianism. Act Utilitarianism would favor #2's post as it improves individual happiness. However, Rule Utilitarianism would favor following the rule of law by suggesting the law provides even greater satisfaction to a greater majority. Lying during voir dire is considered perjury.