The first who reaches that amount of BPs win, it happens a lot (not with 1st but it happens.).
I think it is the last who gets those battle points wins, anyone can confirm which one is true?
So I have 3 different answers out of 3 different posts.
Originally, I thought it was the lower level gets the better place, until a level 60ish ranked higher than me with the same amount of BP...
I had the same question some time ago.
I got an answer from a GM and he said that when tied, they use 3 criterias:
1 - Number of wins
2 - Direct Victory (if they fought each other)
3 - Amount of total life left in all opponents