Denver paid private investors to fix chronic homelessness via social impact bond

By 2015, Denver had identified over 850 people experiencing chronic homelessness, a population with disproportionately high rates of jail bookings, arrests and emergency-room visits. The city was spending heavily on this population every year through policing, jail costs and emergency health services, with little improvement, because permanent supportive housing — the intervention with the strongest evidence of actually breaking the cycle — was expensive to build and scale, and no single department's budget was set up to fund it.

The problem wasn't that the fix was unknown — the Housing First model, giving people stable housing without preconditions and adding intensive support services, had already been validated elsewhere. The problem was that police, jails and hospitals each separately absorbed a share of the cost chronic homelessness generated, and none of those departments individually saved enough by funding permanent housing to justify paying for all of it out of its own budget, even though the city as a whole was clearly losing money to the status quo.

Had private investors front the housing cost, repaid only for measured outcomes, letting the city capture savings that belonged to no single budget.

Investors only repaid on measured outcomes, shifting risk to them.

Repayment from general funds aggregated savings across departments.

RCT gave credible attribution, enabling agreement on success.

Providers had incentive to deliver real results to secure repayment.

When a problem's total cost is real but spread across budgets, fund the fix with outside capital and repay from combined savings.

The program housed 346 people between 2016 and 2020, with 86 percent remaining in stable housing after one year and 77 percent after three years; participants saw a 40 percent reduction in arrests and a 34 percent reduction in police contacts over three years compared to the control group. Denver repaid investors more than $9.6 million against their original $8.6 million, a return of roughly $1 million, and after seeing the results the city separately funded permanent supportive housing for 75 additional people outside the bond structure.