Yesterday (09-DEC-2010) at about 6:42 PM I witnessed a road traffic accident. The accident occurred on the Moorooduc Hwy 11, Southbound, just before the Frankston turn off in lane 2. Two vehicles were involved: a black Ute and a blue Yamaha(?) 1300 In the moments leading up to the accident, I could see the the blue motorcycle was riding along normally in lane two in the left-hand wheel track of the Ute. The vehicles were about 3 cars ahead of me. I became aware that something was wrong: I noticed the black Ute had started driving along the dotted line in the extreme left-hand side of his lane, and he had slowed down to a crawl, leaving an increasingly large gap between him and the cars ahead of him. The motorcycle slowed right down too, and moved to the extreme left hand side of the lane, still keeping the front wheel of his motorcycle behind the Ute. Obviously it was much harder to keep going at the slower speed. The unexpected slowdown probably forced the motorcycle to get closer to the black ute. The time from me first becoming aware that the Ute was driving strangely to moment the accident happened was about 5 seconds. The Ute driver was obviously driving that way in reaction to the presence of the bike behind him. Immediately before the accident, the Ute accelerated quickly and then jammed on his brakes and stopped. The black Ute deliberately caused the accident (i.e. he used his car as a weapon with intent to hurt the motorcyclist). The motorcycle hit the back left-hand corner of the ute. The rider was knocked off. Both lanes of traffic stopped. Some drivers helped pick up the motorcycle and push it to the side of the road. The motorcyclist was not injured; however his motorcycle could not be re-started, so he left his motorcycle at the side of the road and got a lift with another car driver after I gave him my contact details. What a cunt!