Advisor doesn't let me graduate and prevents me from working Posting for my friend
Brief background:
I am in the middle of my 4th year PhD at a US university. I opened up a new direction for the lab, which led me to 2 impactful publications and 1 manuscript ready for submission. 
My lab has 2 lab locations (L1 &amp; L2), and the tools required for my research is only available in L2. Since stay-at-home order started back in March, I was not able to get my full access back to work in the lab. My advisor did not grant my access to L2. He reasoned that L2 is at a max capacity and only people with prelim. data will get priority access. I repeatedly asked for the access (4 times in 6 months) as I have on-going projects and my collaborators have been asking for my devices. Over the past 6 months, he granted access (L1 &amp; L2) to everyone else in the lab, including current members, one new PhD and a new postdoc. Without a choice, I worked only in L1 with very very limited tool and asked one member for help for further process in L2. However, one process takes ~ a month to finish instead of 3-4 days due to this.
In the meantime, he refused to hold meetings with me. Until I repeatedly requested, he would meet me once a while. He met with all other members twice a week. He did not agree/want me work on any of the projects I was working on or proposed at that time. When I asked what kind of projects he would be interested in, he did not know. It seems that he just did not want to give me full lab access and did not want me to work on my projects, basically wasting my time.
Due to all of these, I decided to graduate at the end of 4th year. So I asked him about my graduation plan. He then required me to complete a 4th impactful project and have it published in order to graduate. (This was not even fulfilled by many of his past PhD students.) He provided project suggestions with unrealistic goals (which he agreed). Then he &quot;proposed&quot; to me the projects I proposed to him earlier in my PhD. He said he would consider granting me access to L2 if I can provide preliminary data for these projects. His motive seems very vague and actions are very contradicting. 
I would say that I have done enough (opening up a direction, publishing in high impact journal) to meet the average PhD quality here at the least. Do you think it is appropriate to tell him that I want to graduate? He did not give me same opportunities as the rest while hindering my PhD career. If he doesn't let me graduate, is it okay for me to take the case to the chair and higher-ups?
NOTE: My advisor has been abusive to me (and also other members) since I joined. He has been sued by his students in the past. This is also part of the reasons make me not wanting to continue my PhD longer in this environment.
Let me suggest a couple of things. You may not be happy with the suggestions, I realize, but it is a &quot;safety first&quot; recommendation.
I suggest that you agree to 4th project and that you commit to it. But I suggest that you don't leave it open to a follow on 5th, 6th, etc. Try to come to a firm agreement that this next big thing will be the last he asks and that you will then be able to move on with good recommendations. Hard to get a guarantee on the last part, but it is what you seek.
There are two major reasons I suggest this.
First is that it is now a terrible time to be graduating. Higher education is in flux because of the pandemic and it will take another year for it to settle out. Hopefully it will by then, but a &quot;novel virus&quot; presents an unknown future.
Second is that fighting with your advisor is not a recipe for academic success. Going to the chair with a complaint might poison the relationship and leave you without a future path. I don't know if the advisor is abusing you or just thinks that with a final push you can open more doors in the future. Doing more than the average is actually expected, though not always achieved.
If your funding is in place to continue and you want to maximize your future, consider following his advice.
And if you are actually depressed, go see a professional. The university probably has a counseling office for such things. What you are feeling is pretty natural, actually, but you may need advice about how to get through it.