I apologize, I was reading this thread for a long time, but I suddenly felt that some things by Dazai_Osamu needed to be adressed.
First of all, I need to adress how you use the obvious manipulation, by calling this certainly illegal by real world standarts detention facility (or prison) as "Gulag". Please, google what Gulag is. You obviously use this termine to show how "inhumane" are Damian's actions. But Gulags are labour camps. And they were so notorious precisely becasue of insane amount of labour that prisoners needed to do there. IT simply does not suit Damian's prison.
Secondly, to explain how Damian should "face the consequences" no matter hypocrisy, you ignore the key fallacy there - you substitude concepts of how law, justice and morality works in our, real world and DC world. As dietrich said, heroes in DC world exercice things that in real world would make them "face the law" (even Superman and his Phantom Zone - how it is different??). Even DC government, body of law you might say, has freaking Suicide Squad and can't do a thing over 1000+ serial killers and psychos in Gotham, - not very lawful, realistic and straight-forward. What you said would hold if this happened in real life, but it is not out of ordianry in DC, so what "bad publicity" Damian gave to superheroes again? And who can judge such cases of superheros in DC world? It's like famous killer judging you and putting you in jail for armed assault, both government and adult superheroes are losing their legitimacy to judge in this questions, if you take all facts.
And I don't understand your very harsh judgement of Damian from moral point of view in this case, as he was not holding bank robbers or petty thiefs there, he got Deathstroke and Black mask - serial killers, pretty much undetainable by common justice system of DC world. I personally see this as a Damian trying to reach next step in progression, as previously he just preferred to eliminate the threat, but going in the wrong direction without proper guidance. Now, kid is trying hard to reach new moral hights, struggling, while criminals and killers who he could stop with one swift movement of his blade run around and murder people. Batman would certainly recognize that in his own blood son, if he was written by competent writer, as he faced this struggle on his own.
But I would agree that, of course, Damian is bad, bad boy and heed go to good, good court and face jutstice, if he suddenly teleported to our world and made that same stuff. But the key point here - is that he is out there, in DC, with morally dubious heroes and governments giving themselves bad publicity every day with their actions.
But I agree, that Damian definetly needs to faced the consequences from his dad, what he was doing with his prison is just not right. I think, Tomasi's Batman and Robin run did a decent job there, in my opinion, on Batman teaching and parenting Damian, but didn't left Damian off the hook for his actions as well. That Batman would punish Damian not becasue he broke his rules or some code, but becasue he would worry over direction his 13 years old son is going.
But current Batman firing or punishing Damian sounds to me like father, who left his family for his new lover, but suddenly coming back just once and just to go hard on his 13 years old son for being a bully and troubled child in school.