There are more than $28 million worth of outstanding parking tickets owed to the city of Denver. The implementation of a new ordinance late last year allows Denver parking officials to enter delinquent tickets on a person's credit report, and this has helped recover more money from recent violators.But 7NEWS Investigator John Ferrugia has found there is a loophole in the system that allows some people to avoid paying up.Because tickets are written to specific license plates, some drivers have found a way to avoid paying hundreds of dollars in fines -- just change their license plate.Records show that Ron, whose last name was not used, has accumulated dozens of parking tickets since 2004 -- all on his 1994 sport utility vehicle. But all $1,950 worth are under his old license number. And he has no new tickets under his new license number.In June 2005, Ron got new plates when he transferred ownership to his fiancee."So if they were looking for your old license on the street to give you a boot ...?" Ferrugia asked."Yeah, that wouldn't happen," Ron said."It's gone?" Ferrugia asked."Yeah," Ron said."So, basically, they haven't sent you any notices since you got rid of the license?" Ferrgua asked."They haven't sent me nothing," Ron said.7NEWS has found that Ron's old license plate is indeed listed on what is known as the "hot list" -- bootable vehicles with $80 or more in tickets."We keep a list of vehicles that are boot-eligible and we track them ... by license plate," said Jim Anderson, acting director of Denver Parking Management."Would you be surprised if I told you that many of the license plates on here -- dozens of them -- don't exist?" Ferrugia asked."No, I wouldn't be surprised at all," Anderson said.Anderson admits that's because there is no mechanism for city parking officials to connect the old and new license plates.So since June of last year, when Ron transferred the license, nobody has called him, nobody has knocked on his door and he has not received any mail or had any contact with anybody who wants him to pay the $1,900 he owes in parking tickets."If in the past six months, year, year and a half, I changed license plates ... ?" Ferrugia asked."It's a problem," Anderson said."Why?" Ferrugia asked."Because we are looking for the license plate the violations were issued against," Anderson said.So if some of the biggest offenders on the "hot list" are people who don't have their license plates anymore, it would seem pretty easy to get out of paying their tickets, Ferrugia said."It's potentially easy," Anderson said.What's more, 7NEWS found that you don't have to sell your car either. You just tell the state Motor Vehicle Division that your plate was lost or stolen."It's plausible that I could simply have 20 to 30 tickets on my present plate and come and say, 'Well, I lost it,' and get a new plate?" Ferrugia asked."Absolutely, easy to do. There's no way for us to prove that you didn't lose your plate," said Joan Vecchi, director of the state Motor Vehicle Division."Is there an interface between the state and the municipality to say, 'John Ferrugia sold his car.' He's got a new license number.' Is there any interface?" Ferrugia asked."Not currently, no," Vecchi said.Records show Cassell, whose last name 7NEWS is not using, owed $750 in unpaid parking tickets when she transferred her car to her mother."Actually, I got a new car as well and no one said anything when I went to register my new car. 'Hey, you have an outstanding balance on your parking tickets,'" Cassell said."What you are talking about is a license plate hold. Colorado doesn't have it," Anderson explained."We are talking about millions of dollars that we have to pay a company because we had no system in place, and we still don't have a system in place to track me if I change my license plate because this system is based on license plates, correct?" Ferrugia asked."Right," Anderson said."But no one ever said anything to my mom or me when she switched the plates over, about paying the tickets," Cassie said.Denver is currently spending big money to track past violators and make them pay. Why? Because there is not an efficient system for making drivers pay up front.Other states, including Iowa, New York, and Maryland, have a link between state licensing and municipal governments, which make sure you can't get new plates until you pay your tickets.In Colorado, Denver has no authority to do that. It would take a law voted on by the Legislature. So until then, many people will continue to avoid paying their tickets and that costs the city millions in lost revenue. Have a question or comment on this story? Or have a story idea or news tip? Contact us by calling 303-832-TIPS or E-mail us.