One of your rights when you go to trial for a criminal offense is that you get to have a jury of your peers. They are the ones who hear the case and then decide if they think you are guilty or not. What does it really mean? What is a jury of your peers?
Essentially, it's just a way to get a fair jury made up of citizens who could be considered peers of the person who is on trial. This is a way to reduce the chances of bias in the jury.
For instance, the court cannot take different jurors off the jury simply because of their ethnic background. In one famous case, an African American defendant originally had four African American jurors, but all four of them were removed. An all-white jury eventually convicted the man. He then appealed to the Supreme Court and won.
That case does not mean that the age, race or gender of the jurors has to be the same as the person on trial. However, it sets the precedent that these issues cannot be used specifically to remove people from the jury.
If a woman is on trial, for example, she can't exclude females from the jury. That said, the defendant's gender does not mean that she automatically gets a jury of all female jurors. Her "peers" can include a variety of citizens.
This is a bit of a complex and sometimes contentious issue, and it's important to have an experienced criminal defense attorney who will work to ensure that you get a jury that will be fair.