"Nobody is above the law because of where they live, who they are, wealth, fame, celebrity or even philanthropy," said Judge Steven O'Neill.
The dismissal was announced by Dallas Police Chief Reneé Hall on Twitter.
Some pregnant women may need to be tested more than once, the CDC said.
Sex stereotypes may account for why men dominate science and math, the researchers say.
The victim's dad looked in the backseat of the vehicle and "saw that his son was in his daughter's lap and there was blood everywhere."