Chicago police filed charges Thursday against four young adults accused of beating a young man with mental health issues, an attack broadcast via Facebook Live.
Looking back at his administration's accomplishments, while laying out a road map for future reforms, the president leaves office with an emphasis on reforming the American justice system.
DNA evidence won Lawrence McKinney his release in 2008. He's battling to finally clear his name and receive compensation for decades of wrongful imprisonment.
The US has sentenced fewer people to death and performed the fewest executions since the 1990s. Although attitudes are changing, other factors contribute to the significant decline.