Tylor Chase is back sleeping on the streets of Riverside, and there’s nothing police can do to help the former child actor because of California laws, TMZ has learned.

Riverside Police Department spokesman Ryan Railsback tells us … the former “Ned’s Declassified” actor is desperately in need of long-term care, but the penal laws prevent cops from forcing Tylor into a mental health or substance abuse treatment facility.

“Mighty Ducks” star Shaun Weiss — a major advocate for Tylor — says a mental health crisis team recently placed Tylor in a 72-hour involuntary psychiatric hold, but they inexplicably released him back to his homeless existence. TMZ obtained video of Tylor taking a nap Monday on a stoop in front of a building.

Railsback tells us police can’t help Tylor — legally speaking — because he’s not considered gravely disabled or a danger to himself and others. Not only that, but Railsback points out Tylor politely declines all efforts by the authorities to get him off the streets and into a facility, explaining that homelessness is not a crime.

And get this … Railsback says that even if police arrested Tylor for possessing certain narcotics or drug paraphernalia, the charges would be misdemeanors and he would be released soon after receiving a summons.

As we reported … Tylor has been a transient in Southern California for quite some time while allegedly struggling with meth addiction.