Dozens of scholars of crime -- organized by the Crime Lab of the University of Chicago -- have written a joint letter to Vice President Biden to urge him to include research issues in the Obama administration's proposed response to gun violence. The letter focuses on restrictions on the use of National Institutes of Health funds for research that might be used to advocate for gun control. Further, it noted repeated efforts by gun supporters to block funding of research on guns by the Centers for Disease Control and Prevention. The "politically motivated constraints" have limited research that could help the country prevent gun violence, the letter says.