The way the law works unless you are an immediate threat to yourself or others they can't commit you.
They can't commit you, sure, but depending on the content of the videos could that not have provided sufficient cause for a search warrant?
I don't know if a video is considered probable cause to have a search warrant.
To obtain a search warrant, an officer must first prove that probable cause exists before a magistrate or judge, based upon direct information (i.e. obtained by the officer's personal observation) or hearsay information. Hearsay information can even be obtained by oral testimony given over a telephone, or through an anonymous or confidential informant, so long as probable cause exists based on the totality of the circumstances. Both property and persons can be seized under a search warrant. The standard for a search warrant is lower than the quantum of proof required for a later conviction. The rationale is that the evidence that can be collected without a search warrant may not be sufficient to convict, but may be sufficient to suggest that enough evidence to convict could be found using the warrant.
So when they did a welfare check and he didn't display signs of violence etc. There was really nothing they could have done.
Taken from CNN: Brown said Rodger told deputies it was a misunderstanding and that he was not going to hurt anyone or himself. Rodger said he was having troubles with his social life.
"He was articulate. He was polite. He was timid," Brown told CNN on Sunday.
There was nothing in his behavior to suggest he was violent, and the deputies "determined he did not meet the criteria for an involuntary hold," Brown said.