Simplify the following text for a Grade 15 native English-speaking person.
Original: James Callaghan , then Home Secretary , sent him to implement the Hunt Report , which introduced the standard British rank system for police officers in Northern Ireland and disbanded the controversial Ulster Special Constabulary .
Simplified: James Callaghan , then Home Secretary , sent him to carry out the Hunt Report , which introduced the standard British rank system for police officers in Northern Ireland and disbanded the controversial Ulster Special Constabulary .