Steve-O insists police should be THANKING him for doing a high-flying backflip off a San Antonio bridge this weekend -- into four feet of water -- telling TMZ, thanks to him, the entire city now knows ... that bridge should really have "no diving" signs on it.
San Antonio police are currently investigating the incident -- a rep for the SAPD tells us, they're trying to determine how Steve-O should be punished ... because backflipping off that bridge isn't just illegal, it's extremely dangerous.
But Steve-O says that's BS -- telling us, it's dangerous because the city never posted signs on the bridge, warning people that the water below is only 4 feet deep.
He adds, "They've given no indication that people shouldn't jump, and done nothing to warn anyone about the serious dangers of that shallow water. Very irresponsible, indeed."
Steve-O says his video -- shot for his new YouTube channel -- has raised awareness about the dangers of San Antonio bridge jumping ... and he should be rewarded.