the mapping police violence team compiles data on police incidents using nongovernmental tall databases. leading the project is a policy analyst. tell me what the data is you have compiled? >> we have been able to compile data from the two most comprehensive crowd source databases, the killed by police database and the fatal encounters database. mernl them together to create the most comprehensive set and finished the work of oh coding by race to identify over 91% of the folks in the database and determine if they were unarmed or arm aed at the time they were killed by police. it relies on media reports and has been checked by 538.com which found the data is 100% accurate. >> give me the big story out of the data. the question i have asked over and over we don't have are the answer to is are things getting worse? >> we know police killings have risen slightly.