Could very well be the case. There are still laws in place which say refugees who enter Germany from a 'save nation' should be rejected. Now if you take a look at a map of Europe, that basically means all refugees, other than quota refugees(Kontingentsfluechtlinge), a limited number who are officially brought to Germany in a controlled way. Parliament never voted on changing or suspending such laws and the German chancellor doesn't have a lot of executive privileges compared to the US president or the French le President. I don't know a lot about US law, let alone German law.
But I know that there are reputable lawyers in Germany who said it was unconstitutional. Others say it wasn't.