OKLAHOMA CITY — A request for detailed information about every voter in the U.S. from President Donald Trump’s voting commission is getting a rocky reception from states — and he’s not happy about it.

Some of the most populous states, including California and New York, are refusing to comply. But even some conservative states that voted for Trump, such as Texas, say they can provide only partial responses based on what is legally allowed under state law.

“Numerous states are refusing to give information to the very distinguished VOTER FRAUD PANEL. What are they trying to hide?,” Trump said in a tweet Saturday.

Given the mishmash of information Trump’s commission will receive, it’s unclear how useful it will be or what the commission will do with it. Trump established the commission to investigate allegations of voter fraud in the 2016 elections, but Democrats have blasted it as a biased panel that is merely looking for ways to suppress the vote.

New Hampshire Secretary of State Bill Gardner, a Democrat who is a member of Trump’s Presidential Advisory Commission on Election Integrity, defended the request Friday. He said the commission expected that many states would only partially comply because open records laws differ from state to state.

“If only half the states agree, we’ll have to talk about that. I think, whatever they do, we’ll work with that,” said Gardner, adding that the commission will discuss the survey at its July 19 meeting.