Following the threat of a potential court fight from a federal lawsuit, the state Attorney General announced Thursday the state will establish new limits on using newborn blood samples in criminal investigations. The blood spots will also be retained for two years in a policy change, officials said. The spots were previously stored for 23 years. “The Newborn Screening Program is an important public health program — and it is crucial for the success of the program that its information is kept private,” said Attorney General Matthew J. Platkin. “Today’s Directive adds new limits to ensure law en…