Amnesty International just released on December 18 a study on abuse and harassment on twitter account of female politicians and journalists in the US and the UK. Realised through the collaboration of thousands of crowdsourced volunteers labeling tweets from the database and the machine-learning expertise of the London branch of ElementAI, branch driven by my friend Julien Cornebise with the main purpose of producing AI for good (as he explained at the recent Bayes for good workshop). Including the development of an ML tool to detect abusive tweets, called Troll Patrol [which pun side is clear in French!]. The amount of abuse exposed by this study and the possibility to train AIs to spot [some of the] abuse on line are both arguments that support Amnesty International call for the accountability of social media companies like twitter on abuse and violence propagated through their platform. (Methodology is also made available there.)