He was joined by the cities of Long Beach, Los Angeles and Oakland, and the Los Angeles Unified School District in arguing that the move is unconstitutional and did not follow proper legal procedures.
"This is yet another unconstitutional power grab by a president who is desperate to shift political power away from jurisdictions that have significant numbers of immigrants," said Los Angeles City Attorney Mike Feuer.
The U.S. Constitution requires that each state's congressional representation be based on all residents regardless of their eligibility to vote, including the "entire immigrant population not naturalized," they said.
Aside from possibly costing California a congressional seat, Becerra noted that the census count guides the distribution of $1.5 trillion in federal funding. An undercount would endanger many billions of federal dollars that flow back to the state to fund vital services, he said.
The census results also will help decide how many votes each state has in the Electoral College.
Census data is confidential and can only be used for statistical purposes, Becerra said, urging residents to complete the census forms if they have not already done so.
"Do not succumb to the intimidation," he said.