AUSTIN (KXAN) - The Austin Police department is still trying to collect hundreds of thousands of dollars in unpaid bills uncovered by a KXAN investigation.  In May 2012, the department was trying to collect more than $800,000 stemming from officers working security and traffic control for special events.

The new list of unpaid bills, provided to KXAN by APD, shows the new balance of money owed to the department is $544,862.77. One-third of that is money that has not been collected from events prior to Octover 2006, before the department switched to a digital accounting system from a paper and file one.

"When we saw our name on the list we immediately called APD," said Michelle Graham, the CEO of Bounce, a communications and event planning company in Austin. Bounce owns and operates the annual Keep Austin Weird Festival and 5K. That event is on APD's list of unpaid events, showing the festival still owes $4,204.45 from the event in 2004.

Graham said her company did not get involved with the event until 2010 and she knew she was not responsible for the bill.

"We knew that it wasn't us that was the proper person to be billed and wanted to do two things: one, get it out of our name, because it shouldn't be under the Keep Austin Weird Fest name and help them hopefully track down who it was," said Graham.

Neither Graham, nor APD has been able to determine for sure who was responsible for paying the bills for the Keep Austin Weird Festival in 2004.

"Over the last couple of years, APD has made big strides in their special event department to improve things," said Graham. "The crew they have working there is amazing so I can understand their frustration as well- trying to reconcile all of this."

Reconciling the accounting mess of the pre-2006 era has been a challenge for the department. Legally, the debts cannot simply be wiped off the books, but in many cases, the department cannot find old invoices or other accounting records to prove who owes the bills.

Republic of Texas Rally President Jerry Bragg says he is a victim of bad accounting under the old APD system. Department records show ROT Rally organizers owe more than $30,000 for security and traffic control from their events in 2005 and 2006.

"I've searched my records and I have no record of ever getting billed- I think the city is a little bit embarassed about it because they can't prove they ever billed it or if I owe it," said Bragg. "We're kind of at that stage where we're trying to figure out and sort out if we owe the money and if we do, we'll pay it."

APD is still sorting out a $320.66 bill they say the Austin Symphony Orchestra owes for their 4th of July concerts in 2006 and 2007. The Symphony disputers the charges, arguing they had a deal during those years that the city would cover the costs. This unpaid debt is now tied up in the city legal department and could go before the City Council, which has the discretion to waive the fees.

Since the KXAN investigation began in February 2012, APD has collected more than $400,000 in outstanding bills. In just the last month, they cleared $3,447.61 from events dating back to 2005. Applied Materials wrote a $747.15 check for services related to their 5K back in 2005. The Alzheimers Association paid $861.40 for an outstanding bill related to their Memory Walk. The Frank Erwin Center has taken care of their portion of an $8,042.24 for the Ringling Brothers Circus back in 2007. That check was written to APD for $1,838.46. Ringling Brothers still owes the balance and tells APD the check is in the mail.

APD points out that one-third of the money owed to them- $180,264.89 is for accounts prior to 2006- before the department began using the digital accounting system.

The Austin Police Department is working with organizations who have outstanding bills, but has changed its policy when it comes to granting permits. An organization more than 90 days overdue on a bill will not be granted a permit for a special event.  APD said there are exceptions if the organization cooperates in the process.

Overall, the APD claims to have a 94 percent collection rate when it comes to billing for special event security and traffic control.