In 2019, California had the highest population of unauthorized immigrants, at around **** million. The overall figure for the United States was estimated to be around ***** million unauthorized immigrants.

The estimated population of unauthorized immigrants in the U.S. stands at around ** million people. Although the number has stabilized, the United States has seen a spike in migrant encounters in the last few years, with over * million cases registered by the U.S. Border Patrol in 2023. This is a slight decrease from the previous year, when there were over *** million cases registered. Due to its proximity and shared border, Mexico remains the leading country of origin for most undocumented immigrants in the U.S., with California and Texas being home to the majority.

Immigration and political division

Despite the majority of the population having immigrant roots, the topic of immigration in the U.S. remains one of the country’s longest-standing political debates. Support among Republicans for restrictive immigration has grown alongside Democratic support for open immigration. This growing divide has deepened the polarization between the two major political parties, stifling constructive dialogue and impeding meaningful reform efforts and as a result, has led to dissatisfaction from all sides. In addition to general immigration policy, feelings toward illegal immigration in the U.S. also vary widely. For some, it's seen as a significant threat to national security, cultural identity, and economic stability. This perspective often aligns with support for stringent measures like Trump's proposed border wall and increased enforcement efforts. On the other hand, there are those who are more sympathetic toward undocumented immigrants, as demonstrated by support for the Deferred Action for Childhood Arrivals (DACA) program.

California is home to 12 percent of the nation's population yet accounts for more than 20 percent of the people living in the nation’s hardest-to-count areas, according to the United States Census Bureau (U.S. Census Bureau). California's unique diversity, large population distributed across both urban and rural areas, and sheer geographic size present significant barriers to achieving a complete and accurate count. The state’s population is more racially and ethnically diverse than ever before, with about 18 percent of Californians speaking English “less than very well,” according to U.S. Census Bureau estimates. Because the 2020 Census online form was offered in only twelve non-English languages, which did not correspond with the top spoken language in California, and a paper questionnaire only in English and Spanish, many Californians may not have been able to access a census questionnaire or written guidance in a language they could understand. In order to earn the confidence of California’s most vulnerable populations, it was critical during the 2020 Census that media and trusted messengers communicate with them in their primary language and in accessible formats. An accurate count of the California population in each decennial census is essential to receive its equitable share of federal funds and political representation, through reapportionment and redistricting. It plays a vital role in many areas of public life, including important investments in health, education, housing, social services, highways, and schools. Without a complete count in the 2020 Census, the State faced a potential loss of congressional seats and billions of dollars in muchneeded federal funding. An undercount of California in 1990 cost an estimated $2 billion in federal funding. The potential loss of representation and critically needed funding could have long-term impacts; only with a complete count does California receive the share of funding the State deserves with appropriate representation at the federal, state, and local government levels. The high stakes and formidable challenges made this California Complete Count Census 2020 Campaign (Campaign) the most important to date. The 2020 Census brought an unprecedented level of new challenges to all states, beyond the California-specific hurdles discussed above. For the first time, the U.S. Census Bureau sought to collect data from households through an online form. While the implementation of digital forms sought to reduce costs and increase participation, its immediate impact is still unknown as of this writing, and it may have substantially changed how many households responded to the census. In addition, conditions such as the novel Coronavirus (COVID-19) pandemic, a contentious political climate, ongoing mistrust and distrust of government, and rising concerns about privacy may have discouraged people to open their doors, or use computers, to participate. Federal immigration policy, as well as the months-long controversy over adding a citizenship question to the census, may have deterred households with mixed documentation status, recent immigrants, and undocumented immigrants from participating. In 2017, to prepare for the unique challenges of the 2020 Census, California leaders and advocates reflected on lessons learned from previous statewide census efforts and launched the development of a high-impact strategy to efficiently raise public awareness about the 2020 Census. Subsequently, the State established the California Complete Count – Census 2020 Office (Census Office) and invested a significant sum for the Campaign. The Campaign was designed to educate, motivate, and activate Californians to respond to the 2020 Census. It relied heavily on grassroots messaging and outreach to those least likely to fill out the census form. One element of the Campaign was the Language and Communication Access Plan (LACAP), which the Census Office developed to ensure that language and communication access was linguistically and culturally relevant and sensitive and provided equal and meaningful access for California’s vulnerable populations. The Census Office contracted with outreach partners, including community leaders and organizations, local government, and ethnic media, who all served as trusted messengers in their communities to deliver impactful words and offer safe places to share information and trusted messages. The State integrated consideration of hardest-to-count communities’ needs throughout the Campaign’s strategy at both the statewide and regional levels. The Campaign first educated, then motivated, and during the census response period, activated Californians to fill out their census form. The Census Office’s mission was to ensure that Californians get their fair share of resources and representation by encouraging the full participation of all Californians in the 2020 Census. This report focuses on the experience of the Census Office and partner organizations who worked to achieve the most complete count possible, presenting an evaluation of four outreach and communications strategies.

As of 2023, 27.3 percent of California's population were born in a country other than the United States. New Jersey, New York, Florida, and Nevada rounded out the top five states with the largest population of foreign born residents in that year. For the country as a whole, 14.3 percent of residents were foreign born.

This paper examines disparities in preventive care utilization among Latino immigrants, differentiating between naturalized U.S. citizens, permanent residents, temporary status holders, and undocumented immigrants. We analyzed data from the 2015–2016 California Health Interview Survey (CHIS), a cross-sectional, representative sample of California residents. Our sample consisted of 5,513 respondents who self-identified as foreign-born Latinos. We examined three measures of preventive health: annual checkups, flu vaccinations, and access to mammogram screenings. We applied weighted logistic regression to estimate how immigrants’ odds of receiving annual checkups and flu vaccinations in the past year, and mammogram screenings in the past two years, differed by legal status after controlling for various sociodemographic and health factors. We found that naturalized citizens and lawful permanent residents (LPRs) report higher unadjusted odds of having annual checkups (citizen OR = 3.23, p = 0.000; LPR OR = 2.03, p = 0.000), flu vaccines (citizen OR = 2.14, p = 0.000; LPR OR = 1.62, p = 0.000), and mammograms (citizen OR = 3.24, p = 0.000; LPR OR = 1.95, p = 0.005) relative to undocumented immigrants. However, immigrants with temporary legal status do not differ significantly in their rate of preventive care utilization relative to those who are undocumented. This suggests that precarious legal status, rather than outright undocumented status alone, contributes to disparities in preventive care. After controlling for sociodemographic, health status, and health access factors, legal status disparities in flu vaccinations lose statistical significance, while naturalized citizens continue to have higher odds of annual checkups (OR = 1.46, p = 0.032) and mammograms (OR = 2.69, p = 0.000) and permanent residents remain more likely to receive mammograms (OR = 1.68, p = 0.05) relative to undocumented immigrants. Our findings underscore the need to address access to and utilization of preventive care among legally vulnerable immigrants.