A landmark verdict in Federal District Court in Brooklyn Thursday holding gun makers liable for shootings because of negligent marketing practices is likely to encourage many more lawsuits using the same legal approach.

While industry executives expressed confidence that the Brooklyn verdict would be overturned, the plaintiffs' success, in the first gun trial using the novel claim of negligent marketing, poses a serious threat to the gun makers as more suits are filed.

The success against gun makers came much more swiftly than in suits against the tobacco industry that pioneered the negligent marketing approach.