The enormous US prison population, the world's largest, partly reflects harsh sentencing practices contrary to international law, such as disproportionately long prison terms and mandatory sentencing without parole. Those behind bars include a growing number of elderly people, whom prisons are ill-equipped to handle, and youth under age 18 held in adult prisons. Unauthorized immigrants and their families in the United States are vulnerable to abuses stemming from an outdated, ineffective immigration system that deprives them of basic rights, and increasing numbers are held in detention facilities. A number of abusive counterterrorism policies have continued under President Barack Obama, including detentions without charge at Guantanamo Bay.