I am amazed at the wrong information presented here. Charter school are not simply public schools operated by a person or group. They are entirely free to decline admission to anyone who doesn't fit their criteria. As they have their own curriculum and discipline that can, and usually does, differ from the public school system they effectively exclude the difficult student.
One misbehavior, gone. Parents don't actively support the school, gone. Have autism, we don't have a program for that, gone.
For example our local
Villages Charter school has this rule:
"Parent Involvement Information: Qualifying parent(s) (father/mother/stepfather/stepmother) and/or spouse (or designated adult if single parent) must complete *20 hours every year for each school on campus where children are enrolled. Parent involvement is mandatory for your child to attend The Villages Charter School"
Do they provide all the special ed services a regular public school is required to offer? No
"While VCS does not provide all services or programs for students with disabilities, the Sumter County School District(SCSD) has programming available for any student need."
Every complaint about charter school effectively draining the public schools of the easily educated student and leaving behind those students with behavior problems, learning problems, disinterested parents, significant autism.... etc. is easily proven just by reading the school website. And anyone who thinks this is not what is dooming the public schools is ignoring reality.