I am the PhD student who has been in the lab longest. I take this to mean you have no authority over him?
This morning I told Barney I needed to talk to him, and in a calm, quiet voice told him the following:
"Please take your things and move to other bench. This sounds like an order? Is there a rule that he's breaking? Or just your preference? I'm asking you to do this for two reasons: one, the bench is becoming very crowded and two, I am not at ease working next to you.
I am still angry about what happened last week. This is good Your behaviour was unprofessional, irresponsible and frankly, rude..." I think you went a bit far here. You're scolding him. That's something that should be left for his superiors.
At this point Barney interjected with "But I apologized for that!"
I continued, in the same calm, quiet voice:
"Actually, no you didn't and please let me finish what I have to say. I don't know what you were thinking when you decided to work in Apparatus when you knew perfectly well I was in the middle of working there.Good That kind of behaviour is not acceptable in our lab, and cannot repeat itself. Again, this is acceptable if you are in a position of authority in the lab/over him. If not, I think you went too farYou endangered me, yourself and the rest of the people in the lab by not following regulations. If you are unsure of how to work with something, ask someone to help you or to supervise you as you work. Now, please take your things and move to the other bench you will be more comfortable there."
He kept nodding and saying "OK, OK, OK." I normally doubt people actually understand when they reply like that, but here's hoping.
He has been avoiding me all day since. Maddie thinks he is afraid to come near our part of the lab.
There's "authority" and then there's "authority." Shopaholic may not be in a line management position above Barney on an org chart, but that doesn't mean that she doesn't have authority. As the senior PhD in the lab she's got plenty of authority over a new Master's student (i.e. someone with an undergrad degree and no real experience.) A formal, documented hierarchy is not the only way that authority works.
In a lot of situations, it was the OP's right and responsibility
to do the scolding. I know that if I were the lab manager or PI I would expect
my senior PhD to put the guy in his place and not bring issues like that to me.
I don't have direct-line authority over the developers on my project. I report directly to the Director of Engineering and they report up through someone else who reports to the DoE. I can guarantee you that none of them would ever get away with refusing to do what I told them, based on "you're not the boss of meeeeeee." Both officially and unofficially, the DoE and the development manager have delegated their authority to me in certain matters. Even more importantly, they do what I ask because I'm the senior, most experienced person there. My authority comes more from who I am and less where I show up in an org chart. I've worked in many places where there were people who had no titular authority, but nevertheless had tremendous influence. Ignoring them would be extremely foolish.
Barney's making the classic blunder of someone new to the workforce: He's failing to assess the whole
workplace. Assuming that someone doesn't have authority simply because they lack a title is a very, very bad mistake. Witness the PI telling Shopaholic that she can tell Barney what to do and where to go and the PI will back her up. The last thing a newbie should do is annoy someone and then
find out that they've got the bosses ear. Trying to dominate someone without understanding the whole environment can lead to much worse than the "bad dog" he got. Again, from my own experience, I get asked frequently to assess people who don't report directly to me. Annoying me could result in a bad review, failure to renew a contract or a lukewarm recommendation. Even if I don't have the final say, if I said "fire them," I know that would be given a lot of weight.
I realize that lots of people work in very structured, hierarchical environments, where if someone isn't explicitly higher than them on the food chain then they have no authority. There are many people who prefer that kind of environment. The rest of us work in messier places where lines of authority aren't so clearly drawn.