Why must members of Congress fly first class?

Rep. Gwen Graham (D-Fla.) introduced legislation Tuesday that would prevent members of Congress from using taxpayer funds on first-class plane tickets. The bill would also ban lawmakers from using government funds for long-term car leases for personal use.

"It's a commonsense idea that Republicans and Democrats can both agree on: members of Congress shouldn't be able to charge taxpayers for first-class airfare or long-term personal car leases," said Graham, who will likely be one of the most vulnerable House Democrats in the next election cycle.

I cannot conceive of any "commonsense idea that Republicans and Democrats can both agree on," but I wish her the best of luck in pushing this legislation.