I assume you don't think that every crime should carry the same punishment. So in a simplified sense of error, they are both equally wrong. However, the consequences of their actions were asymmetrical. We don't even know if the property suffered any harm before, during or after the scuffle.
One side being more wrong doesn't make an excuse for either side. There isn't a finite amount of punishment that has to be apportioned according to blame. Each side, if a crime was judged to have been committed, would face a separate process with a separate jeopardy.