UCSF statewide study: housing shortage, justice involvement and behavioral health drive homelessness in California

Dr. Margo Kushel, director of the UCSF Benioff Homelessness and Housing Initiative, presented a statewide representative study to the Council on Criminal Justice and Behavioral Health on March 22, 2024, saying the homelessness crisis is “driven by the lack of supply of affordable housing.” The study interviewed 3,200 people and conducted 365 in‑depth interviews to describe who is experiencing homelessness and why.

Kushel told council members that California has about 20 units of housing affordable to every 100 extremely low‑income households, leaving the state roughly 1,000,000 units short for the lowest‑income Californians. She said 90% of people experiencing homelessness are California residents and 75% lost housing in the same county where they became homeless.

The research documented stark racial disparities: 26% of adults experiencing homelessness identified as Black (compared with 7% statewide) and elevated shares of Native/Indigenous respondents. The population is aging (median age 47); among single adults, 48% were age 50 or older.

Kushel highlighted the overlap between homelessness and criminal legal system contact: 79% of the study participants had been incarcerated at some point; 37% had a state or federal prison stay and 77% had a jail stay. She said nearly 19% of participants became homeless the day after discharge from an institutional setting of three months or longer and that only a minority received reentry help: “19% of those leaving jail and 18% of those leaving prisons had said that they had received any support” to obtain or recertify benefits, and similar low shares received help reconnecting to health care or housing.

Behavioral health problems were common: Kushel reported high rates of trauma, post‑traumatic stress disorder diagnoses, suicide attempts and psychiatric hospitalizations. She said 48% of participants met a broad threshold of significant behavioral health need (regular illicit drug use or heavy episodic alcohol use, hallucinations, or recent psychiatric hospitalization). Methamphetamine use was prominent among those reporting regular illicit drug use; 11% of participants reported surviving an overdose during their current episode of homelessness.

The study identified key barriers to rehousing: cost (89% cited inability to afford housing), credit or eviction history (49%), lack of documentation (53%), and discrimination (43%). Kushel said criminal records and prior incarceration frequently block access to housing and employment and argued these dynamics make reentry a critical intervention point.

On policy, Kushel emphasized housing supply and targeted prevention. “Everything—every pathway through ending this—has to flow through increasing access to affordable housing options,” she said, urging expansion of permanent supportive housing and prioritized interventions for people leaving incarceration. She reviewed evidence from a Santa Clara randomized supportive‑housing intervention that produced large, sustained gains in housing retention among the highest‑needs people approached for the program.

Council members pressed on interim solutions while housing is developed. Kushel endorsed a dual approach: prevent new homelessness where possible and expand outreach, harm reduction, and hygiene and medical services for people currently unsheltered. On shelters she said some people prefer shelter while others avoid shelters because they can be crowded or trigger trauma; she cautioned policymakers not to conflate reluctance to use shelters with opposition to housing.

The council and public commenters raised concerns about mortality in targeted programs and the timeliness of interventions for people released from incarceration. Kushel said mortality findings in some targeted programs were disappointing but suggested research design and population selection (very high‑acuity participants) influence outcomes and that earlier rehousing tends to reduce mortality risk.

The presentation is part of a broader set of findings that Kushel and her team plan to publish in deeper reports focused on experiences with the criminal legal system later in 2024–2025. The study and recommendations are available through the UCSF Benioff Homelessness and Housing Initiative.