While the Department of Homeland Security is working to make deportation practices more humane, critics opposed to these efforts have called attention to a report stating that Immigration and Customs Enforcement officials released 36,007 convicted immigrants in 2013. The report, issued by the Center for Immigration Studies, has intensified a tension between immigration activists and advocates for lower levels of immigration. Those in opposition to President Obama’s efforts argue that Homeland Security and ICE should be strengthening its immigration enforcement efforts, saying that the release of undocumented immigrants causes a threat to national security. But the report itself is highly suspect, with little documentation (other than a generic citation that the data come from ICE) and no breakdown showing how many of the purported criminal aliens are actually in the country illegally. An immigration advocacy organization, the American Immigration Council, has issued its own critique of the CIS study, suggesting that all those criminal aliens cited in the report have completed their sentences or paid fines and the overwhelming majority have committed non-violent crimes. Moreover, though they have been released from custody, according to ICE, those who had committed serious crimes continued to be monitored by GPS or other means.