Watch the testimony on mute. When you look at the faces you can tell how much emotion is really there. Do you see sadness, grief? Anyone, even someone not trained in reading language can detect emotion simply by looking at a person while they speak without listening to what they say.
Then the next thing you can do is imitate the body movements. Look down, refuse to look at someone, do not speak with any illustrators, read from a prepared statement and see what emotion you are feeling.