Berlin, May 5: With the Cambridge Analytica scandal revealing massive misuse of Facebook users data, Germany’s justice minster has said that the social network must bring changes and become more transparent with users. In a letter to Facebook CEO Mark Zuckerberg, Katarina Barley also said that the social network needs to give its users “real control” over their data and set up new internal supervisory mechanisms to ensure that formal guidelines are upheld in Facebook’s dealings with third party advertising clients.