Private parking companies are requesting hundreds of thousands more drivers' details from the DVLA than two years ago, prompting calls to ensure motorists are not being "fleeced" with "hidden or unclear" penalties.
Anyone can request vehicle keeper information from the DVLA to find out things like who may have been responsible for an accident, and private parking companies often use the service to help them issue parking tickets.
Labour has said the latest statistics suggest the industry is pursuing claims against more and more people as concerns increase over the number of parking tickets being issued.
In 2013 there were 2.2 million electronic requests for vehicle keeper data specifically from private parking companies.
But in 2015 there were more than 3.6 million requests.
Meanwhile, the total number of chargeable requests made to the DVLA for vehicle and driver information in 2009/10 - not just from private parking companies but from everyone - was just shy of 2.9 million.
In 2014/15 that figure stood at 6.3 million.
Shadow transport secretary Lilian Greenwood has called on the Government to make sure information is only handed out when "absolutely necessary".
She said: "These figures reveal an extremely worrying increase in the number of requests for drivers' personal information.
"They will add to concerns that there has been a huge rise in the number of parking tickets issued in recent years, which will come as no surprise to people who have already been stung by hidden or unclear parking penalties.
"It is vital that the DVLA and ministers make sure that personal information is only shared where it is absolutely necessary and that ordinary car owners are not being fleeced by parking companies."
The increase in requests for information has led to surging levels of income for the DVLA.
The figure for the total amount charged for processing requests for information has leapt from £9.4 million in 2009/10 to about £15 million in 2014/15.
The Government has stressed that the DVLA does not make any profit from the process.
Transport Minister Andrew Jones said in a written response to a parliamentary question on the subject: "It is important to note that although the DVLA is permitted to charge a fee for the release of information, it is not permitted to profit from it.
"Fees are set to recover the related administrative costs for the different types of requests for information and the fee levels are regularly reviewed as the cost base changes over time.
"This means that it is the applicant and not the taxpayer who funds this activity."
Mr Jones also said there are a range of organisations that legitimately request data from the DVLA including insurance companies and toll chargers.