A) Demonstrate that a Problem Actually Exists (offense, pt 1).
Goal: So you've got a new idea--so what?  What harm is there in the way things are done now?  What's wrong with just keeping things the way they are?  If it's not broken, we don't want to fix it.  Demonstrate that the problem is real. 

Possible Strategies:
Give anecdotes about individuals harmed. 
Give statistics about individuals harmed. 
Show that the way things are done now harms many people, or if it only harms a few people, it harms them deeply.

B) Demonstrate the Cause of the Problem  (offense, pt 2).
Goal: Show that the problems are tied to the way things are now. 

Possible Strategies:
Provide evidence that shows that the harm described in part A is caused by the  particular law, method, or attitude which the paper is arguing against.

Provide evidence that shows that although the plan presently used is reducing the problem, there remains a gap between results and the desired goal.   

Goal:  Demonstrate that the current theory is broken.  So what if you've got a new idea?  What's wrong with the old idea?   If it's not broken, we don't want to fix it. 

Strategy 1) Show how the current theory fails to explain the actual observations in the field or in the laboratory. 

Strategy 2) Challenge the traditional evidence.
Show that previous investigators used faulty evidence. 

Show that previous investigators intentionally falsified evidence.

Show that traditionally used evidence can't be applied to this case.

Strategy 3) Challenge traditional scientists' interpretation of the evidence; challenge the link between the evidence and their claims about the evidence. 
Show that previous investigators had preconceived ideas that warped their interpretation of the data. 

Show that traditional arguments are outdated. 

Show that traditional arguments don't really apply to this case.