While some governments pursue voice pattern collection for identification or authentication in limited situations, there are significant challenges to applying such technology for crime control and surveillance. The Chinese government has stepped up the use of biometric technology in recent years — including the construction of large-scale biometric databases — to bolster its existing mass surveillance and social control efforts. Both collection and use should be limited to people found to be involved in wrongdoing, and not broad populations who have no specific link to crime. The company states it can develop artificial intelligence systems that can handle minority languages, including Tibetan and Uyghur. There have been documented cases in which activists and netizens have been sentenced for their peaceful expression on communication tools, including on social media applications like WeChat. Compared with other biometric databases run by the police, the voice pattern database appears to be less established, with fewer samples in it.