Naya Rivera Wrongful Death Lawsuit Filed on Son's Behalf, Claiming Unsafe Boat

Ryan Dorsey has filed a wrongful death lawsuit on behalf of Naya Rivera's son ... claiming the boat Naya was in before she drowned was unsafe.

Naya's ex-husband filed the docs Tuesday on behalf of his 5-year-old son Josey Hollis Dorsey, claiming Ventura County is responsible for her death because the boat Naya and Josey were on in Lake Piru did NOT comply with safety standards.

In the docs, filed by Ryan's attorney Amjad Khan and obtained by TMZ, Ryan claims the boat was “not equipped with a safely accessible ladder, adequate rope, an anchor, a radio or any security mechanisms to prevent swimmers from being separated from their boats, nor any flotation or lifesaving devices" in violation of California law.

Ryan's claiming the boat drifted away from Naya and Josey when they jumped into the lake for a swim ... and proper safety equipment could have prevented that. The suit claims the boat was "rocking back and forth forcefully in the current and wind."

Ryan also claims in the suit there were no signs warning of the dangerous conditions of the lake -- and the person who rented the boat to Naya didn't warn her to wear the life vest that came with the boat.

As you know ... Naya and her son were reported missing on July 8. Her body was found in the lake on July 13. Josey was able to get back in the boat, and when authorities arrived for a check, he told them he and his mom were swimming and he didn't know what happened to her. She had disappeared below the surface.

According to the suit ... at least 26 other people, from children to fit adults to elders, some wearing life jackets and others not, have drowned in Lake Piru since its recreational facilities opened.