Parents might be getting divorce need help

So I'm 21 years old and the only child of this family. My dad has always been a pretty big douche to me, and a big control freak. Things always have to go his way, and the career path I'm on currently is also set by him and I have no interest in it. Even though I have my own share of problems with him, this shouldn't be about me. My parents have been fighting a lot the past few days, and I think it's reaching a breaking point. Things may even escalate tonight, so I'm not sure if I'll be able to add as much info as I want in order to get the best advice possible, without things being out of context. Basically my dad is a real estate agent, and things haven't been too well the past few years. I'm just naive enough and my dad is really good at keeping up his image enough that I didn't notice. In 2013 there was some really big deals happening, and our financial situation basically turned around. So he was thinking of buying an iPad, because it's something every realtor has. I think that since we did come into money, I can understand him wanting to get something nice for himself. But my mom disagreed, and said he shouldn't buy it, as he has no use for it. Her main point was that most of the other realtors sell houses, and uses the iPad in a useful way to show pictures off to potential buyers. Now my dad is the type of person to get angry easily, yell a lot, and verbally abuses the both of us. Sure it's not the most pleasant thing in the world to be constantly insulted by him, and I'm pretty sure it's the root cause of my self esteem issues. He was getting pretty mad, saying he's the only one that works and makes the money, so why shouldn't he be able to spend it as he pleases? For the past few months he's been getting increasingly irritated at my mom's role of being a housewife only. She has no job, but she used to back before I was born. We immigrated to Canada about 10+ years ago, but she still doesn't know too much English. I have to add in so much context for everything I mention, so I'll try my best. Basically since he's such a control freak, she has no cell phone, a hand me down desktop I used to use before I got a new one for university, and technically no car of her own (my dad has two and the non SUV is hers). She's really restricted in her freedom of making friends, buying anything (always has to save receipts) and in general. I'm also very limited in what I can do compared to pretty much anyone else in university. Not allowed to spend my money on hobbies as I please (but I do it secretly anyways), very hard to go out during weekends to meet up with friends so I usually stay on campus for that. Pretty much have to be home before 8 pm almost always. The iPad argument happened on Friday, where we were supposed to have a nice dinner outside, but my dad accidentally locked himself out of the car. Frustrations rose, and after a late dinner, he said told her "I'm gonna tell you again, don't fucking tell me how to spend my money when you don't make any". While I was waiting for the guy who unlocks cars to come though, I was talking with my mom and she seemed increasingly unhappy. She told me she's seriously considering a divorce with him, as things have been getting worse. He keeps getting angrier at her, and verbally abuses her constantly. That night he was yelling at her some more, and my mom called me over and told me exactly what he said to her, which were all big insults. One of which included a 'death threat' but I honestly feel that he would never hurt her that much, and even though it's not appropriate I honestly feel it was due to the high emotions. Yesterday she randomly went out and took the car with her, not really saying where she was going or taking my dad's 2nd cell phone for emergency. He got pretty irritated about this and complained about her to me while driving me to the train station. When I got picked up early that day, because I was apparently getting a new phone (I'm suspicious to this as I feel he's only really nice to me whenever he's angry at my mom, just a few weeks ago he was pretty pissed off at me). It was delayed for a bit due to time restraints, and he mentioned again that my mom just rode off as she felt like. But considering this in context where she was not allowed a lot of freedom for most of their marriage at all, I could understand her position. Today's events are what escalated it. I wasn't there for this at all, and I am trying to explain it as unbiased I can after hearing it from both sides separately. It randomly snowed today and the roads got decently icy. My mom said she's getting a haircut, and was going to take the car. Because of the bad road conditions, he offered to drive her there. Well she's been getting sick of seeing his face or talking to him the past few days so she really didn't want to. After he got dressed he said to hand her the key, and she did. My dad told me she threw it, but my mom says she did not. They were probably talking to each other in angered tones, and not a civil conversation. She said to him "I'm taking the bus to get there" and walked out the door. So my dad got real mad about this, and got in his car to go after her. Now there's some girl who is the gf of one of my neighbors, and she always parks her car right next to the cul de sac. It's always right in the way and you have to be decently careful to go around it. Due to the bad conditions and the angry driving, he smashed his car right into it. Now he's very concerned about his cars, as they're luxury ones and this increased his anger 100 fold. I got picked up in the secondary car and he told me what happened. Now after eating dinner quietly with my mom she's telling me she can't handle this verbal abuse anymore and was about to seriously call the police. I was already having a hard time digesting what happened the past few days, and on Friday with high emotions I even suggested that she get a divorce after seeing how terribly unhappy she was. She also told me she wanted to try and get a restraining order. But I knew if any of these things happened, it would escalate things to such a point where it would be a 0% chance of getting back to relative normality (which really isn't compared to most families). I recommended she calm down and make decisions with a clear head, as this kind of thing cannot be taken back. She agreed, and she said she was actually scared that he'd do something physical to her. Even though I would say I hate my dad when his anger is directed at me and he treats me like absolute garbage, I'm confident that he wouldn't actually hit her. I've made him angry enough for him to start throwing stuff but not directly at me. I did tell her though, if any sort of physical activity starts, then yes, police should be called, but for now, even though verbal abuse is just as serious, I think escalation is uncalled for. There's also a moral dilemma for me. After today when he walked in the house he started just yelling at her, about how he's sick of it all and said he didn't want to see her face. Now I tried to convince him in the car through the whole ride to calm down and not start an argument or say anything, just to walk up, but I couldn't. As I was changing and feeling pretty sober, I randomly hear some voices. It wasn't the TV, and it was her recording him yelling at her on her ipod, and now I can either choose to not say anything or tell him about it, which cements me on a side, which I don't want to take. There's so much missing context here, but this is the best I can do in the limited amount of time I have, as I really feel the breaking point is very very soon. I'd appreciate any advice, any next steps, any guidance at all.

Does your Dad have any Blood Pressure issues? If so do get him monitored soon. As far as your parents splitting up is concerned, its better for them to stay apart since both of them feel that way. If possible arrange for them to stay away from each other and give them a few days to think with a clear head. Clearly tempers are rising and even though he may not have raised his hand on her there is no 100% guarantee that he will not. This is the most difficult time for you but you need to be there for both of them.