Police departments across Connecticut are turning to high-tech GPS darts to track suspects without chasing them. The dart-like trackers, fired from patrol cars, stick to fleeing vehicles and transmit real-time location data. But critics, including the ACLU and public defenders, argue the practice may violate privacy laws if done without a warrant. State police say the trackers are legal in urgent situations. At least 30 devices are being ordered for departments statewide.