If a school has an unusually high suspension/exclusion rate then it will affect the ofsted inspection result, as this is seen as a lack of discipline and control.
I'm not sure if its still in force but if a pupil was suspended for more than five days then the school had to still provide education to that pupil.
Another policy that was in force was if a pupil was permanently excluded, the school had to accept pupils that were excluded from other schools. This rule may have been removed in 2010 as the new Academies didn't have to accept expelled pupils and so an unfair system was in place.
The rules on discipline are at the least confusing and change frequently.
In a time of universal deceit - telling the truth is a revolutionary act. George Orwell
When the debate is lost, slander becomes the tool of the loser. Socrates