If the polish government is getting leaned on by Brussels to increase immigration, then a national referendum could be a good bargaining tactic to go "no can do, my hands are tied" and refuse without having to constantly antagonize the EU leaders pushing them
If the polish government is getting leaned on by Brussels to increase immigration, then a national referendum could be a good bargaining tactic to go "no can do, my hands are tied" and refuse without having to constantly antagonize the EU leaders pushing them