He said that according to nationwide studies of school discipline procedures, white students were most often "referred to the office" for discipline for clearly defined violations such as smoking, using obscene language or vandalism, while black students most often found themselves facing "fairly subjective" charges such as disrespect, loitering or threatening behavior.
"There is no data that shows that African-Americans are suspended more often because they act out more," Skiba said.
Rather than imposing zero tolerance, schools should be working to develop teachers' skills in dealing with students from different backgrounds so that they can defuse situations in the classroom and keep kids where they can learn.
Using a Hammer Too Often?
Even more, Skiba says that zero-tolerance policies have not done anything to improve the environment in schools.
"There isn't any evidence that zero tolerance has made a positive impact, either on school violence or on school behavior," he said. "If anything, it seems to be kind of negatively associated with school behavior or improving school climate.
"It [school discipline] is like a carpenter's tool box," he added. "A hammer is a useful tool for building a house, but it gets pretty ugly if you try to use it for too many things."
The reason, he said, seems to be that suspension is not the most effective form of punishment for students, as indicated by statistics showing that as many as 30 percent to 50 percent of children who are suspended repeat the same infractions once they are allowed to return to the classroom.
"If you've got kids with that kind of recidivism, psychologists will tell you that's not a very good punishment," he said.