Specification 
http://docs.oracle.com/javase/8/docs/api/java/util/List.html#subList-int-int-
says: 

"Throws:
IndexOutOfBoundsException - for an illegal endpoint index value (fromIndex < 0 || toIndex > size || fromIndex > toIndex)"

However it doesn't happen for some lists, please see the following code:

---
        CopyOnWriteArrayList<Integer> list = new CopyOnWriteArrayList<>();
        list.add(1);
        list.add(2);
        list.add(3);
        list.add(4);
        list.add(5);
        List<Integer> newList = list.subList(1, list.size() - 1);
        int fromIndex = 2;
        int toIndex = 1;
        newList.subList(fromIndex, toIndex);
---

No exception will be thrown though fromIndex > toIndex.

The following new JCK8a test will be failing due to this:

api/java_util/concurrent/CopyOnWriteArrayList/index.html#CopyOnWriteArrayList[testSubList3_IndexOutOfBoundsException] 

The problem is seen with JDK8, JDK8u5