ICE issued a generic response that did not challenge Harris' statement that ICE detainers are voluntary.
"ICE has been dedicated to implementing smart, effective reforms to the immigration system that allow it to focus its resources on criminals, recent border crossers and repeat immigration law violators," an ICE statement read.
Immigrant rights advocates say there needs to be a statewide standard.
"Whether someone is subject to deportation as the result of a minor infraction ought not depend on what county the person is in; the Attorney General's guidance demonstrates the need for a statewide policy in the form of legislation such as the TRUST Act," said Thomas A. Saenz, president of the Mexican American Legal Defense and Educational Fund.
The third version of the TRUST Act, or the Transparency and Responsibility Using State Tools Act, was unveiled on the first day of the state legislature last Monday. In essence, the bill would have limited state participation in the S-Comm program.
Two months ago, Governor Jerry Brown, who was attorney general when S-Comm first came to California, vetoed the previous version of the TRUST Act, saying the bill went too far in limiting local law enforcement's discretion. It appeared, though, that he agreed with it in principle.
State Assemblyman Tom Ammiano (D-San Francisco) reintroduced the bill on the first day of the legislative session, emphasizing how urgent it is to act quickly on the legislation.
"I wanted to reintroduce this immediately because these policies have been hurting people every day," Ammiano said. "All of California is hurt every day when we allow families to be broken apart and productive workers to be taken from their jobs in a way that does nothing for safety."
Brown joined ICE Director John Morton on Thursday to discuss the TRUST Act with sheriffs at the California State Sheriffs' Association quarterly board meeting, which was not open to the public.
"The governor had a vigorous discussion with John Morton and the sheriffs," Gareth Lacy, Brown's spokesperson, said. "The TRUST Act was at the center of this discussion and it was detailed, positive and productive."
Neither ICE officials nor the Sheriffs' Association responded to calls for comment.
Reshma Shamasunder, executive director of the California Immigrant Policy Center, was "very concerned" about the closed-door meeting.
"Why was a meeting about a program plagued by a tremendous lack of transparency held in secret?" she asked. "Director Morton has caused tremendous confusion among sheriffs and the governor, and has presided over a heartbreaking spike in deportations. He should not be shaping policy in California."
In response to Harris' directive on the ICE holds, Sheriff Baca, who has been the most outspoken opponent of the TRUST Act, recently said he would no longer honor ICE detainers for low-level offenders.
This announcement was viewed with suspicion from immigrant rights groups.
"Am I the only one skeptical of Baca, who said undocumented immigrants have no rights?" Shamasunder tweeted on Wednesday, referring to previous statements Baca made on a local NPR affiliate.
Finally, in Chicago last week, a federal judge ruled that a lawsuit challenging the legality of detainers could proceed – calling into question the very legitimacy of ICE's power to act.
The lawsuit, which was filed by the National Immigrant Justice Center, "questions the procedure of allowing presumed undocumented immigrants to be held in jail beyond the period established by judges and prosecutors within which their immigration status must be verified," according to EFE.
"This is an important ruling that overcomes a significant obstacle that advocates around the nation have faced as we try to hold the government accountable for its unconstitutional use of immigration detainers," NIJC's Mark Fleming told EFE.