The U.S. House Energy and Commerce Committee held a hearing Tuesday with former Equifax CEO and Chairman Richard Smith.

Equifax faces federal inquiry after the credit reporting agency allowed security breaches that compromised the personal information of more than 145 million Americans. That lost data includes millions of people living in Washington and Oregon.

Rep. Greg Walden, R-Oregon, chairs the Energy and Commerce Committee. He and other lawmakers demanded that Smith give a detailed explanation of how the Equifax hack took place.

“It’s like the guards at Fort Knox forgot to lock the doors and failed to notice the thieves were emptying the vaults,” Walden said. “The American people deserve to know what went wrong. We want a clear timeline of events, and what to expect moving forward.”

Walden and other members of the committee pressed Smith on how Equifax checked its security measures between when the hack happened in May and when the public became aware in August.

Smith said the company had a protocol in place to check for security breaches, but it wasn’t followed.

“I don’t think we can pass a law that, excuse me for saying this, fixes stupid,” Walden replied.

Smith resigned last month over the security breach, and opened his testimony Tuesday by saying responsibility for the massive breach ultimately falls on him.

Tuesday’s committee hearing begins three days of inquiry into how Equifax managed to compromise the data of millions of Americans.