Schuster was directly elected to the German Bundestag on 24 September 2017 for the third time. In the 19th electoral term, he again assumed the function of chairman of the CDU/CSU parliamentary group in the Committee on Internal Affairs. He was also elected chairman of the PKGr. In addition, he was elected as chairman of the first committee of inquiry on the 2016 Berlin truck attack, which is charged with investigating the circumstances of the terrorist attack of 19 December 2016 and, if necessary, drawing conclusions.