While Tesla's response to the accident has been very aggressive (to the point of being rude), transparency is also important. Not being able to talk about an accident for an entire year would be a disservice to the community and most likely lead to rampant speculation considering how high profile these accidents are.
In this case Tesla has handled the entire incident rather poorly, but it makes sense that they would want to abstain from the investigation to be more transparent about what happened. Keep in mind that in a year from now the data about the accident will be mostly irrelevant.