WASHINGTON, D.C. (AP) — Senators grilled Ticketmaster Tuesday about its spectacular breakdown last year during a sale of Taylor Swift concert tickets. Republicans and Democrats on the Senate Judiciary Committee debated possible action, including making tickets non-transferable to cut down on scalping and requiring more transparency in ticket fees. Some suggested it may also be necessary to split Ticketmaster and concert promoter Live Nation, which merged in 2010. Ticketmaster is the world’s largest ticket seller, processing 500 million tickets each year. In mid-November, Ticketmaster’s site crashed during a presale event for Swift’s upcoming stadium tour. The Justice Department has also opened an investigation into the breakdown.