As the Title suggests, the “Calculated Destruction” passive in the Sorcerer (Mage) skill tree affects not only Spell Crit Chance, but also Base, Melee & Bow Crit Chance. I don’t know if that is intentional or not, as the tooltip states:
“Increased Spell Critical Strike Chance per Intelligence: 3%”
I’m unsure whether the issue is in the wording of the tooltip (in that it should state that the Crit Chance is Global, not solely Spell), or that the node is providing Global Crit Chance, when it is only supposed to be Spell Crit Chance (since it’s in the Sorcerer skill tree, which specializes in Spell skills).
Edit: As a note, this is occurring while playing as a Spellblade. I have not checked whether this occurs as a Sorcerer.