AMNA NAWAZ: California voters have narrowly passed a ballot measure that will fund billions of dollars to help the state tackle its homelessness crisis.

William Brangham looks at the initiative that just passed by a razor-thin margin.

WILLIAM BRANGHAM: About a third of the people who are homeless in America live in California.

And, for years, it has been an endlessly vexing problem for the state.

Since many of these people also suffer from severe mental illness and addiction issues, the newly passed Proposition 1 includes a $6.4 billion bond to fund 11,000 housing units and treatment beds.

It also funds $1 billion for homeless veterans.

Today, Governor Gavin Newsom celebrated the victory.

But opponents say it doesn't do enough to keep people from becoming homeless in the first place and that it gives the state too much control over mental health spending.

Christine Mai-Duc has been covering all of this closely for The Wall Street Journal.

And she joins us now.

Christine, thank you so much for being here.

I laid out some of those top-line numbers, but can you explain a little bit more about who this is most intended to help?

CHRISTINE MAI-DUC, The Wall Street Journal: Yes, absolutely.

So, from the beginning, Governor Newsom and all of the allies behind this effort have been clear that this is about helping those who are the most desperate, the most in need of help in terms of mental health services, in terms of substance abuse disorders, and also homelessness, so, basically, kind of these twin crises of substance use disorder and homelessness, really trying to get those folks who are in the most dire of need off the streets.

WILLIAM BRANGHAM: So I have read that it's about - - estimated about 180,000 people who don't have a place to live in California.

Not all of those people are mentally ill or substance abuse issues.

But 11,000 beds or treatment openings doesn't seem like it closes the gap that much.

CHRISTINE MAI-DUC: It certainly isn't going to erase the problem overnight.

And you're right.

Not all of the folks who are on the streets in California suffer from mental illness or suffer from substance use disorder.

What researchers do know is that, sometimes, those two challenges can precipitate about with homelessness or being on the streets can actually exacerbate those conditions.

So, really, what we're looking at here is an attempt to create some of the spaces that are needed for treatment.

WILLIAM BRANGHAM: And what was the opposition to this?

I mean, this seemed like a particularly narrow victory.

How do you explain what the opposition was here?

CHRISTINE MAI-DUC: So, the opposition came from really two distinct places.

One was a number of mental health advocates who were concerned that the portion of this measure that would actually divert some funding away from existing mental health programs and put it toward housing would be detrimental to the mental health system in California.

The tax that was passed in 2004 that funds this that is going to be redirected, it makes up basically a third of the state's mental health system, public mental health system at the moment.

And so there was some concern that current and existing programs might be harmed by that.

And the other concern is that, as California and other states really reexamine what the balance is between kind of compelling people into treatment, kind of certain involuntary methods of trying to get folks off the streets and into treatment, whether for mental health issues or substance use issues, that more of this money might go to locked facilities or promote more involuntary treatment, which is not something that many, many advocates like the ACLU and other civil rights groups support.

WILLIAM BRANGHAM: They're arguing that it's - - that some of those measures might be too coercive for people who don't or may not be ready for that treatment?

Is that the argument?

CHRISTINE MAI-DUC: I think there's always a concern when there's a question over whether someone will be put into treatment or in a facility involuntarily.

Kind of the original sin of all this was the deinstitutionalization during the 1950s and 1960s and the shutdown of a really big mental health kind of system and infrastructure in the state that wasn't really replaced with anything else.

So, going back to those days, in terms of locked institutions, is not really what everybody wants to do.

That said, I think there are some questions.

And this is an ongoing policy issue in California.

There's going to be some laws that are implemented that change what conservatorship means and include substance use disorder among the reasons that somebody can be put under a conservatorship and have those decisions - - and have those decisions made for them.

WILLIAM BRANGHAM: I mean, California is not unique for suffering with these kind of public policy issues, but California has had a very longstanding problem with this.

Does your reporting help us understand why California has been struggling with this for so long?

CHRISTINE MAI-DUC: Certainly, the lack of affordable housing in California really does not help the situation.

There has been an underbuilding in California for decades.

There's, some folks say, millions of units of housing short in terms of the population and what's needed.

And so it's harder to build in California.

It becomes more expensive to build in California.

The state and local governments have tried to kind of change some of the policies and laws to help with that in recent years.

But, really, even as more and more money and billions of dollars gets put toward homelessness issues, folks are falling into homelessness as quickly as we can bring them out in a lot of cases.

WILLIAM BRANGHAM: All right, Christine Mai-Duc of The Wall Street Journal, thank you so much for sharing your reporting with us.

CHRISTINE MAI-DUC: Thanks so much for having me.