According to the official website of the Dominican Judicial Power about their flag: The flag was created by the late Dominican Judge Julio Genaro Campillo Pérez. It was first raised on February 23, 1998.
The meaning of its colors is the following:
Purple: represents the Judgeship
White: represents the lawyers
Blue represents the Public Ministry
The golden scales represent Justice
In the website, it is also explained that the blue of the lower stripe is "Copenhague Blue" The flag should be raised in all Judicial Power buildings and court rooms, next to the national flag. See a really beautiful (and big) picture of the flag online. Francisco Gregoric, 9 November 2005