California's Senate President said the Attorney General's statement is nothing short of blackmail. This includes refuses to detain known felons under federal detainer requests or otherwise failing to comply with these laws.
"Such policies can not continue", Sessions said.
Sessions said that to get department grants, cities must comply with Section 1373, which says that federal, state and local officials may not interfere in the exchange of information with immigration officials about an individual's citizenship or immigration status.
"When cities and states refuse to help enforce immigration laws, our nation is less safe", Sessions said on Monday.
The U.S. Attorney General has announced plans to withhold funds from so called "sanctuary cities" causing reaction around the country. This policy is entirely consistent with the Department of Justice's Office of Justice Programs guidance that was issued just last summer under the previous administration.
The attorney general claimed during that sanctuary cities make the nation less safe.
Speaking at the White House during the daily press briefing, the Attorney General said states and cities will now have to certify that they are not sanctuaries for undocumented immigrants.
"Failure to deport aliens who are convicted of criminal offenses puts whole communities at risk, especially immigrant communities in the very sanctuary jurisdictions that seek to protect the perpetrators", Sessions told a White House news briefing.
The decision is in line with President Donald Trump's executive order from January, stepping up enforcement of existing United States immigration laws.
Meanwhile, municipal leaders gathered in NY vowed to defy Trump's crackdown as they gathered for a small conference that attracted officials from cities including San Francisco, Seattle, Denver, Chicago, Philadelphia and NY. Sessions added that "the DOJ will take all lawful steps to claw back any funds to a jurisdiction that willingly violates 8 U.S.C. 1373".
Despite what AG Sessions implied today, local gov'ts have broad authority to not participate in federal immigration enforcement.