At least this article makes clear that the perp was shot with his own gun.
But still, the article is silent as to whether the cop was armed or unarmed. Tactically, it may be necessary to disarm an attacker rather than attempt to draw a weapon.
The question remains: Does an off-duty Chicago cop dressed as a clown carry a weapon or not? Chicago may be require that their off-duty law enforcement officers disarm. Maybe they do.
I would consider it newsworthy to know whether or not the officer was armed. It would be instructive to recognize that sometimes an attacker must be disarmed rather than drawing a weapon.
On the other hand, it would be instructive to know that even Chicago cops, when off-duty, are at the mercy of armed attackers, and only those physically capable of using the attackers own weapon will overcome the attack.
Both articles are noteworthy for what they don't say.
But still, the article is silent as to whether the cop was armed or unarmed. Tactically, it may be necessary to disarm an attacker rather than attempt to draw a weapon.
In all of the gun disarmament drills I went though, it was always "redirect", "control", "disable the attacker", "disarm". So if a crim shoves a gun towards you, the first effort is to redirect the muzzle, the next move is to control the perp's hand in such a way that he won't get a shot off into you. The third is to beat-the-crap out of the guy either with knees, fists, elbows, whatever until the subject is softened up, then break the weapon out of the crim's hand. Extra points if you can also pistol whip or break off fingers in the process. Given the situation, and since this was a Chicago LEO so every shoot is always a deemed a "clean shoot", empty the magazine into the perp.
Extra points for good grouping and clever shot placement so that your fellow officers won't give you grief after IA clears the shoot.