From Ammoland:

The move for the amendment started in 2015, after the terrorist attacks in Paris.  By the middle of 2016, Czech President, Miloš Zeman was suggesting citizens should be armed “over the long term” and carry pistols in public, to defend against terrorist attacks.

Czech lawmakers approved an amendment that will enshrine the right to use a weapon in self-defense in the Czech constitution – a new right that will be included in the country’s Charter of Fundamental Rights and Freedoms.