KLKN-TV UNL threat assessment expert says reporting warning signs could help slow mass shootings “I think if we have more people coming forward with concerns, that is a sign of progress." April 17, 2021 6:08 pm LINCOLN, Neb. (KLKN) – In the past month, American flags have been at half-staff due to numerous mass shootings across the country, a disturbing trend that has many Americans asking how we can put an end to the violence. UNL psychology professor Dr. Mario Scalora is one of the top threat assessment professionals in the country. He says the key is to try and stop problems before they start.