Oliver could tell Viola had a headache, but that was something he was not inclined to remove from her. Actions had consequences. He'd always taught his children that. He would protect them from the world as much as he could, but he could not always shelter them from their own mistakes, or they would never learn.
And yet Viola had not yet learned -- and was that her fault, or had he gone wrong somewhere, teaching her? He felt a dull pain in his own head that echoed hers; it was his powers' response to the sudden, unwelcome pang of guilt.
He took a breath, easing his way through it. "You lost control of your beams, and blew up a car in front of several witnesses," he finished for her, since she seemed reluctant to come to the disastrous culmination of the night's events.
"Do you know what it takes to cover something like that up?" He sighed, growing agitated. "Agents are going to be tracking down everyone at that rave that might have seen, erasing memories, trying to make sure nothing winds up on YouTube --" He paled; the words came out of him just as the thought occurred to him. The idea of his daughter caught on camera using his powers made him almost physically ill.
"You know what can happen to people who are discovered, Viola," he said, sounding almost more pained than angry.