Katy Perry is being investigated by cops over bombshell sexual assault allegations made by actress Ruby Rose. Wonderwall.com can reveal Aussie police started the process after the actress, 40, filed a complaint. 'The investigation remains ongoing' Cops say they are 'investigating a historical sexual assault.' By: MEGA Rose accused the "Roar" singer, 41, of sexually assaulting her in 2010 during an incident at Melbourne nightclub Spice Market. Perry denies the claims.