U.S. Assistant Attorney General John Carlin said on Monday that more than 110 people have been publicly charged in federal court since late 2013 on counts related to the Islamic State militant group that has overrun much of Syria and Iraq.
Carlin said the U.S. Justice Department needs the American public to be more proactive about alerting federal authorities when they witness someone showing support for foreign terrorist organizations, such as Islamic State, in remarks to reporters at the U.S. Justice Department.
In more than 80 percent of the Islamic State cases that have been prosecuted since 2013, someone in the community of the accused person believed they had witnessed the activity for which the person was ultimately charged, according to Carlin. In more than half of those cases, the witnesses did not report anything.
Many of the Islamic State supporters prosecuted since 2013 have been charged under "material support" statutes that prohibit supporting designated foreign terrorist organizations. No domestic groups have that designation.
Carlin said it would be "dangerous" to criminalize support for certain domestic groups because doing so would infringe on Americans' civil liberties.
But he said it "may be worth" considering a new statute that would enhance sentences for individuals who commit acts of violence in pursuit of U.S.-based extremist ideologies.
The Department of Justice charged 60 people last year, the largest annual figure on record. The number arrested this year has been less than last year's figure.