On September 19, 2007, at 1204 Pacific daylight time, a St. Clair Ragtop-01, N3134Q, collided with terrain during an aborted landing at Perris Valley Airport, Perris, California. The pilot was operating the airplane under the provisions of 14 CFR Part 91. The private pilot and one passenger sustained serious injuries; the airplane sustained substantial damage. Visual meteorological conditions prevailed and no flight plan was filed. The pilot departed from Perris earlier that day. The pilot reported that he had recently purchased the airplane. The pilot had about 400 hours total flight time. He received instruction in the airplane and had accrued approximately 3 hours in it at the time of the accident. He and his passenger departed for the local area flight and flew to Lake Elsinore, California, where they did a full stop landing and noted no problems. Then, they returned to Perris and he noticed that a tractor was parked at the end of the runway. Upon touchdown, the pilot stated that the braking system did not work so he elected to abort the landing. He applied power and as he turned the airplane to the left, the left wheel impacted a fence post, and then the airplane collided with the ground. The pilot stated that they had completed maintenance on the braking system a couple of weeks prior to the accident. The brake is operated by a handle on the yoke. The pilot further stated that there were no problems with the braking system upon landing at Lake Elsinore. A witness was driving south when he saw the airplane landing on the dirt runway to the north. The airplane appeared to touch down, and he expected that it would turn off of the runway so he parked his vehicle. He momentarily looked away, and when he looked up he saw the airplane flying by. It climbed about 8 feet and then nosed left to the ground. The Federal Aviation Administration accident coordinator responded to the accident site. Due to damage sustained to the airplane during the accident, the reason for the braking malfunction could not be determined. The pilot did not complete the NTSB Pilot/Operator Aircraft Accident/Incident form as requested.