These policies are promoted as preventing drug abuse and violence in schools. Critics say zero tolerance policies in schools have resulted in punishments which have been criticised as egregiously unfair against students and teachers, especially in schools with poorly written policies. Consequently, critics describe these policies as "zero-logic policies" because they treat juveniles the way that adults would be treated — or more harshly, given that children are seldom granted full permission to speak up in their own defense to adults with authority over them. Many people have been critical of zero tolerance policies, claiming that they are draconian, provide little if any benefit to anyone, contribute to overcrowding of the criminal justice system, and/or disproportionately target people of colour, particularly people of African-American and Hispanic descent.