A father who lost his son in a hit-and-run accident turned detective when he discovered that the man banned from driving for killing his 14-year-old was driving again.

Bernard Proctor tracked Gordon Stratton with a camera and video equipment in a specially converted van to prove Stratton was violating the driving ban, a court heard this week.His evidence helped send Stratton back to prison.

"I sat in my van and used a telescopic lens to get pictures of him coming out of a pub and driving away," Proctor said.

"I lost count of the footage of video film I used, but it was all worth it."

Stratton, 29, pleaded guilty to two charges of driving while disqualified and was sentenced in south London's Croydon Crown Court on this week to nine months in jail. He was also banned from driving for another year.

Prosecutor Peter Finnigan said that Tim Proctor was killed in 1982, and Stratton was sent to prison in 1983 for nine months and banned from driving for 4 1/2 years for causing deaths by reckless driving. He was again disqualified from driving for three years in 1985.

Finnigan said Proctor heard Stratton was still driving, and tracked him for several months to gain the evidence he handed over to police.

The judge, Sir Donald Farquharson, told Stratton: "What is particularly distressing is that having caused the death of a young boy one would have thought that in those circumstances you would have been particularly careful not to get involved in driving offenses again."

Proctor said Stratton should have gotten a longer jail term.

"He is clearly a danger on the roads," he said after the hearing.