The black boxes should be like any other evidence. If probable cause exists, then a subpeona should be used to see them. Having said that, people should know whether or not their vehicles have them and if so, they should disable them. And, under no circumstance should the guv't require them to be in a person's vehicle (I don't know if they do). I don't want the guv't telling me I have to carry a snitch tattletale around with me.
all cars have them and they cannot be disabled.
But as they are designed to operate brakes airbags and in some cases engines, removal becomes less and less possible.
Further, depending on WHEN you remove it, you could be charged with destruction of evidence. Sort of like hillary "losing" the records...