If the school doesn't specify double spaced, then you could probably submit a single spaced statement and not be dinged for "breaking the rules". That said, double spaced is the standard. And it is for a reason...It's easier to read. If you're an admissions official and you have a lot of apps to read through, you don't want to struggle. Best case they won't care; next best, they won't read it; worst case, they won't appreciate it. Just understand that sometimes you have to rewrite stuff during this process. I have a really well written personal statement (at least I think so). It's about 2 1/2 pages. I loved the schools that had a max of 4 pages, but there were some schools that had a 2 page or a 500 word limit, so I reqrote a different statement for those schools. It takes a lot of time, but I figure it's the first commitment I will make to my education in law.