A Swindon motorist has 39 penalty points on his or her licence - the most in Great Britain - but not been banned.
A Freedom of Information request to the DVLA showed 638 drivers in Bristol, Dorset, Wiltshire, Somerset and Gloucestershire have 12 or more points.
Twelve points usually means a temporary ban for a driver unless they can prove it would cause exceptional hardship.
A court decides if a driver is banned and the Magistrates' Association agreed the Swindon case needs investigating.
The DVLA's response to the Freedom of Information (FOI), from BBC West, did not say which offences the penalty points related to and gave no further information about the driver from Swindon.
It explained that although it compiles the figures on court cases involving driving offences it has no influence on verdicts.
Elliot Griffiths, from the Magistrates' Association, said: "I accept that something appears to be wrong with [the figures in the Swindon case] and they need to be looked at.
"I can't even conceive how somebody can have 20, 30, 40 points and not be disqualified.
"I can't work it out. I'd be very interested to see how it happened."
Cath Harley, from the road safety charity Brake, said the figure was "shocking".
"It's completely unacceptable that people are clocking up to 39 points on their licence," she said.
"Again this is a risk to other road users and it's absolutely vital that people who exceed 12 points on their licence do in fact receive a driving ban."
The DVLA added courts can exercise discretion and not disqualify the driver in a "small percentage of cases where the driver has accumulated 12 or more penalty points."
A driver with 12 points can argue disqualification would cause exceptional hardship - either financial or personal.
If the court finds the hardship argument applies, but the driver then accrues further penalty points within three years, the same exceptional circumstances cannot be cited again.
The DVLA said the figures were current as of 24 March 2011.
- 27 January 2011
- 4 January 2011
- 6 May 2010