[senco-forum] guidelines on supporting SEN pupils in mainstream units in Scotland

Please can someone tell me where in Scotland to find guidelines on the 
provision that schools are expected to make for the management of SEN  
pupils with a history of violent behaviour in mainstream schools/ units.

Is it the principal educational psychologist in a region who has 
responsibility to draw up such arrangements?  Or the school HT?

Thanks for any enlightenment

Elizabeth