Pot grower charged with murder

Several readers sent me this story: Pot grower faces murder charges for firefighter deaths.
Daniel Brough was growing marijuana in a basement closet in Philadelphia. The lamps dried out the wood in the closet and started a fire. Two firefighters (Fire Capt. John Taylor and firefighter Rey Rubio) died in the resulting blaze. Now Brough is being charged with third-degree murder, marijuana possession, involuntary manslaughter and causing a catastrophe.
Brough was stupid and created a dangerous situation. But that list of charges is a bad case of prosecutorial piling on in a very emotional situation. I’d like to know if the charges of murder, involuntary manslaughter and causing a catastrophe would have been filed if the cause had been someone carelessly leaving a candle burning.
One other point. Please note that these two firemen are also drug war victims. Marijuana hurts nobody, and there would be no reason to grow it in a closet if it was legal.