What is comparative? It is "comparing" two or more different things and saying which is better. Simple enough right? But it's a surprisingly important part of debating.
It is very easy to give the judges simply a long list of good things and bad things without saying which I should care about more. On very simple things (e.g. there will be more dead people) it is okay to let the judges do this themselves, but the more complex arguments you make the more you need to say what is important and why.
This is also where impacting comes in, translating a harm into obvious real world terms. Random example, if you tell me X will result in disillusionment with state institutions, that sounds vaguely bad. But I'm not very sure how much I care, but if you tell me that because people are disillusioned with the state they won't report crimes to the police, they will turn to vigilante justice, and that will cause bad things, I now know why I care.
Comparative then is taking the impacts of two different points, or of the opposing sides of the debate and saying which is more important. Example: "Even if we buy their analysis, their only harm is that a small number of people will be upset because of an abstract violation of their bodily autonomy, compare that to the harms we bring you of mass death if people are not vaccinated."
|CC - Flickr user Infobunny|
Another way in which a point can be "non-comparative" is if it is true, but it is true on both sides of the debate, so it doesn't matter. Example: "They say that our policy will economically coerce people, but people aren't making a free choice in the status quo anyway so that point is non-comparative." If you explain why the form of coercion on their side is more harmful, or affects more people, or whatever it is then comparative.
Comparative is essential in a summary speech, where you are explicitly telling the judges why point X beats point Y and why. But it is also important to do in every speech. Its also an element of judging, deciding what is important in the debate, but if you do that yourself you can ensure that the judges think your stuff is the most important.