Проверка Laravel по записям базы данных

Problem is how to validate by Database model, I have model "Emails". I just want to people can register if their email already in our Email model.

Таблица базы данных электронной почты

Schema::create('emails', function (Blueprint $table) {
        $table->increments('id');
        $table->text('username')->nullable();
        $table->text('fullname')->nullable();
        $table->text('description')->nullable();
        $table->text('email')->nullable();
        $table->timestamps();
});

Auth @ RegisterController

protected function validator(array $data)
{
    return Validator::make($data, [
        'name'     => 'required|max:255',
        'email'    => 'required|max:255|unique:users',         here i guess
        'password' => 'required|min:6|confirmed',
    ]);
}**strong text**