I (and others) posted previously about JHU safety, which can be read here: http://talk.collegeconfidential.com/johns-hopkins-university/1821701-questions-about-baltimore.html#latest
Basically, don’t conflate city crime statistics with campus safety. Unless you plan on living in the most dangerous parts of a large urban city then you won’t be exposed to the level of crime that is being reported. Schools are rarely located in the dangerous parts of town and this is why the US Government requires all schools to report crimes on and around campus to better inform students and their families on the risks of attendance. In this regard Hopkins is a very safe school (the safest? No, and of course bad things do happen) because it is in a “bubble” of safety from the increased security, the significantly more expensive property values in the immediate area and its relative distance from the downtown (which can attract some bad actors). Make sure you are making informed decisions about the school itself and not the city as a whole - there’s a surprisingly big difference when you to start to discern between the two! Hope this helps!