Who Is Really At Fault In This Car Accident?

[paomigz15]

I was involved in a car accident yesterday, at around 7pm, along EDSA (between Buendia and Ayala). I was traveling within my lane at about 10 to 20 KPH (I'm the driver of the Mazda white) when another car suddenly moved inside my lane and went to a full stop. I tried my best to avoid him by applying my brakes as well and turning my wheels to the right as fast as I can, but I still hit his right rear (side only). The result of the accident were just scratches on both cars since the accident was more of a side swipe.

The other driver's stand is that the car in front of him applied a hard brake so he also went to a sudden full stop. But my stand is I was driving safely within my lane when he suddenly entered my lane and went to a full stop which resulted to the accident. There were two MMDA enforcers who attended us but they didn't want to give their opinions on this matter, and they were just asking us settle this on our own or they could bring us to their office in MMDA, Guadalupe for further investigation if it's not settled. We've been trying to settle the matter for an hour and I was just exhausted so I just agreed to pay him 2,000 pesos so we could go. I actually only paid him 1,000 pesos for now, and I said that I'll just deposit the other 1,000 pesos to his bank account since I don't have 2,000 pesos at that time. I actually have 2,000 pesos but at the back of my mind, I just want to go home and I don't want to pay him since I think that it's not my fault and I want to ask other's opinion on this before I pay him in full.

My question is, is this really my fault since I was the one who hit his car even if I was clearly within my lane when he entered my lane unsafely? I have attached the pictures of the accident for your reference. I would really appreciate your feedback.

Thank you so much!