Can you elaborate on what you mean by "extremely unsafe" in that statement?
Accidents and electrocutions... trams are notorious.
I should note that Baltimore is another city that I personally know of with a "light rail" system... Savannah boy mentioned San Fran... forgot about that one too, but never been so couldn't speak from personal experience on that.
Trams in various forms are extremely popular in Europe and are being used as solutions to reduce gridlock in several US cities. Many cities in the US that deal with surburban sprawl have begun developing park and ride initiatives e.g. Charlotte recently finished construction of a 15 station light rail system, Atlanta has a small system and they are looking to expand, San Diego has a system that is being expanded, Dallas, Sacramento, etc. Once engineered correctly, they reduce GHG production and in most instances, decrease transit time.
With respect to safety, I disagree with your assessment. Several studies have shown that instances of tram accidents actually decrease as the population becomes familiar with practices. Additionally, it appears that pedestrians in general (both US and Europe) have less respect for light rail systems than for buses. High rates of accidents at stops, crossings and stations result from people jumping out in front of the vehicle assuming it has a shorter stop distance. Even with that, modern rail systems have a much lower fatality risk per vehicle per mile than bus systems which is remarkable considering the fact that bus systems cover far more distance than rail systems.
Another reason for the seeming bad reputation of tram systems is the extent of injury once an incident does occur. Most of those vehicles are not equipped with protective shielding to reduce exposure to the iron wheels which are much less forgiving than bus tyres.
As for electrocution risks, I'm not aware of peer reviewed studies that compare to other modes of public transportation.