Yes and no. If he took off his collar then there would have been an "uh oh" reaction from the audience but there are many possibilities like:

He was very hot and need to loosen up lol

He was going to beat up Dante badly.

He was going to kill him.

He was going to torture him to get some Intel out of him given that Gabe was watching the interview video and may be onto something.

He was going to let Dante go for some reason.

It's unclear whether he was already planning to kill all along or was it an uncontrollable rage right at that moment. He was talking about second chances a second prior and that stabbing came out of nowhere.

 

I think his mind was pretty much made up already when he entered the cell, that he was going to kill him. He easily turned Dante’s words around to apply for himself: he got a second chance not just from Rick back in the day, but now, to do right by Rosita and CoCo, as he blames himself for failing them by letting Dante into the community.

 

I hope he ditches the collar now.

 

On Talking Dead Seth said that Gabriel went there planning to kill Dante. He left the cell door open so that if Dante made a break for it he could use the excuse that he killed him while trying to escape. But if that didn't happen he was ready to do it anyway.

Yes, and the second chance was about himself, but it played perfectly in the scene. It's also Gabe recognizing that his more passive approach wasn't working.

 

Not just that. Revealing him to be the Silence the Whispers vandal, he also caused dissension in the community causing them to distrust Lydia even more which led to her brutal beating, the one lady's accidental death by Negan who defended Lydia which also caused Carol to take action.

So when you think about it, Dante won bigtime with his actions.

To answer the op Father Gabriel did the right thing. Dante didn't deserve a voice of reason because his actions were beyond unreasonable.

 

Maybe we could say that the laws drawn up for the community apply only to members of the community during peace time, not to enemy spies. There is no Geneva Convention for Whisperers while engaging in hostilities, and they are engaged in hostilities. Why should he have been allowed to sow further confusion and fear with a formal hearing? He was caught red handed after he murdered Siddiq and he confessed what his mission was.

I think they should have gagged him, tied him to a stake, read out his crimes to the community and then let every member walk by and stab him....(sorry Jon Snow, lol). Gabe could have been first in line but you can understand his sense of horror and remorse for allowing Dante to stay. Sort of I caused this problem and I’ll take care of it attitude. Whether or not it was rash is now moot but I doubt anyone would blame Gabe after it became common knowledge as to Dante’s identity. Gabe could make a case for martial law being applied by the acting council.

 

The difference as I see it is that clemency, to a certain extent, was extended to Negan AFTER the Saviors lost the war. The war was over and Rick’s mercy could prevail over his wrath, although if I remember correctly, not all community members were happy with that decision at the time but Rick was the acting leader so they kinda fell in line.

It seems to me they were going to cut fingers and ears off the Whisperer captive to get him to talk. Is there anything about torture in the laws? It’s not an exact parallel to their past civilization. You can still light up a whole group of people who threaten your family and that’s that.*cough Carol cough* After the mass piking at the fair, the sickened community members from Dante’s water sabotage, Alpha’s continued threats and attacks, etc. I don’t think you’d have the division you speak of. I’d wager most of the people would actually like revenge and come together if they’re informed about what happened behind the scenes. It was an execution of an enemy spy. There might be some mumbling but they’ll fall in line behind Gabe in Michonne’s absence.

 

Do we know what laws do they have to handle a case like Dante?

I mean, was he supposed to have a public trial, with an appointed 'lawyer' to speak for him or him speaking for himself, trying to explain? I would suspect, his crimes would be read out in public (perhaps this has already been done off scene after Dante was captured. In fact, Dante admitted his crimes already), then the council would vote about Dante's fate. Perhaps, the council came to a tie and Gabe had the final vote to cast (like he said last time when Gabe said he would think over it overnight and gave time for everyone to come to a clear head). So, if Gabe decided on a death penalty, then it is not too much over the board that he went into the jail to finish Dante instead of a public execution.
(BTW, this reminds me of Maggie's public execution of Gregory)

 

Yes, and we have to remember that for the last 8 years the communities were experiencing peaceful conditions. They’re at war now, and because the number of people in each community is rather small, and there is no military so to speak or more than one holding cell, some things might have to be adjusted to fit the circumstances. Eight years are a drop in the bucket when it comes to establishing a working democracy. During a war with a very aggressive and murderous group, I don’t think you can extend them the same rights until their leaders are defeated and the threat eliminated.

 

I agree that mob justice is often misguided resulting in many an innocent person losing their lives. A small “mob” almost beat Lydia to death. Dante wasn’t pleading innocent though. He cheerfully spilled his guts about his exploits so there was no need to consider him innocent until proven guilty. He did this in front of other council members. Gabe acted as judge and executioner. Perhaps it wasn’t his place, but I would bet money that nobody cares.

 

Perhaps, but I think Gabe came to the conclusion, after watching Dante’s interview tape, that the man was a skilled liar. Didn’t he ask Dante something to the effect, was anything you said real? What kind of information could they believe out of his mouth?

 

I’m not sure what kind of government they're trying to establish here. It’s not a democracy....more like an Oligarchy. Power rests with a small number of people, which in Alexandria is the council. They have a loose confederacy with the other communities, one of which doesn’t even exist anymore.

I don’t think we’ve been privy, as an audience, to exactly what laws Michonne has included in her charter. But they’re not in a place yet, emotionally, to go on with business as usual pre ZA.
When Michonne told Virgil she was gonna cut him if he didn’t answer her questions, no one batted an eye. This is still a primitive civilization, where safety is the number one priority and the “leaders” will do what’s needed to maintain that. With larger groups, if they exist, things might be different.

 

A fascinating debate above, both of you with absolutely valid points and to decide where we stand is indeed challenging. I would agree with @Neuropyramidal in principle, but this situation here was so extreme that I'd side with @purriwinkle, that the charter might not include laws that apply here. We have never seen the full charter, where it stands on death penalty and who decides. Interestingly, one of the main incentives for drawing up the charter was Michonne witnessing Gregory's impromptu execution.

This is the first statement of the charter:

"Any person who would live in peace and fairness, who would find common ground, this world is yours by right. We stand together for life not death, in this new world. Together, we make this world bigger. The future is ours as we hold onto our faith in one another with everything ... concentrate our band, we establish this Multi-Community Charter of Rights and Freedoms."

So there's a possible contradiction right at the beginning: as Dante didn't live in peace and fairness and didn't seek to find common ground, he had no right to this world. Does this also mean he had no right to anything in this world? "We stand together for life not death" hence we shouldn't have death penalty? But what if the person in question stands for death? Like Dante? In order to stop him, to be pro-life, do we need to kill him? It's all a little washy-washy, and we never got to see the actual paragraph on what to do with the enemy who murders and puts members of the community in mortal danger.

What we did see though is that death penalty was *considered* and voted on by the council in Alexandria (Negan's case). There was no formal discussion in case of Dante. I agree that there should have been. Dante was led back to the cell to await this decision by the council. Gabriel should not have gone in to kill the prisoner. The council should have decided formally, and as death penalty to murderers is obviously considered by them viable, in this case they most likely would have all voted yes. As far as the manner of execution, there should be an agreed procedure. But until now, they never had to do it. I expect such detail is not included in the charter.

So yes. Gabriel was wrong to do it, and he will suffer the emotional consequences, because he knows he was wrong to do it. Yet, at the same time, he was so very right to do it, at a basic, primitive level, and we could all feel how right it was, (which in itself is horrifying). We as humans are so complex and terrifying.

It boils down to our stand on death penalty as well. In principle, I'm personally against it. Yet. A selfconfessed serial killer? Like Dante? And I need to get off my liberal soap box. He had to die for what he did. I don't seem to have any doubt. No right for life in our world, in their world. Especially not in their world where resources are scarce. Why should he be kept alive and fed by the very people he had harmed? Should he have had a "cleaner" execution? Probably. But did he deserve what happened to him? Absolutely. So... it's very confusing. No wonder the world still can't agree, and there are so many different approaches to this day.