DENVER - When you call 911 you typically expect police to show up fairly quickly. In Denver, some calls classified as less urgent wait for two, three and four hours before an officer responds.

"We work for the citizens, and they deserve better," said detective Nick Rogers, President of the Police Protective Association, the union for Denver Police.

9NEWS obtained Denver Police call logs for a three day period in April. They show some of the calls classified as lower priority by the police department sitting, waiting to be dispatched for several hours.

DPD rates calls based on emergency.

Shot, bleeding, dying rates 0 to 2. Those calls don't wait. The rest are classified as lower priority. The ones listed on documents obtained by 9NEWS range from 3 to 8.

According to the April 24 call logs, police didn't respond to a burglary in the 3000 block of West Mississippi Avenue for three hours and 48 minutes.

A theft the day before in the 300 block of North Broadway wasn't dispatched for two hours and 20 minutes.

April 25, a sex assault call was on hold for one hour 37 minutes.

"We have response times two to three hours on non-emergent calls. That's ridiculous," PPA Vice President Lt. Vincent Gavito said.

"None of these calls should take three hours to get to," Denver Police Chief Robert White said. "There will always be mitigators, that some of these non-emergency calls took a lot longer than what they should, but my commitment to this community, to the men and women on our police department, we're going to minimize those mitigators."

The police union blames the new staffing structure called "team policing." Officers work a beat together and have the same days off.

The union says this structure isn't flexible enough and leaves police short-handed. They wrote a letter to Chief White Monday expressing their concerns and criticizing the current use of the concept.

"Quite frequently, I'm staffing 10 and 11 officers on the street. Where a year ago, I was staffing 14 and 15," Lt. Gavito said. "That is a 20 to 25 percent reduction. It's simple math. It's going to stack up the calls."

Gavito and Rogers say the union supports the "team concept's" use at a different time for the Denver Police Department, when it has full staff.

The PPA says the department is short-staffed. Right now, DPD has 1,355 sworn officers. Its authorized strength is 1,426. Approximately 537 officers respond to 911 calls. Its first academy in five years is taking place right now. The new recruits won't be able to take to the streets for about a year.

The chief told 9NEWS, patrol was very important and he's been adding officers to it as much as possible.

"A team policing concept is officers, and a supervisor, are locked in to the same shift, to the same assignment, and the same days off. They work the same days of the week together," Gavito said. "In theory, it's a very viable concept and it has worked in other cities across the country. However, it requires a good deal of man power to provide sufficient coverage 7 days a week. In Denver, we do not have sufficient staffing numbers to implement this team policing concept to a satisfactory staffing."

"To equate team policing to the delay in response time [is] not only unfair, it's an inaccurate assumption," Chief White said. "[It] has zero to do with team policing concept. The team policing concept in the long run is going to make it better not make it worse. I believe they're telling you that because it has had an impact on their ability to have flexibility of choosing what days off they want. It's also their continuation of resistance to change, change that holds them more accountable, change that makes us more accountable to this community, change that makes them more accountable to their supervisors."

Chief White provided 9NEWS statistics that show a 13 percent reduction in violent crime. White said he attributed the drop partially to team policing. The Chief compared January through April of 2012 and 2013; he said since its implementation in January, team policing has lowered the number of calls for service and increased officer-initiated calls, meaning police are more proactive.

"As we continue to transform where we need to be, I suspect we'll continue to see that success," White said. "Our success will even be greater. The sooner we can hire these officers the mayor has committed to I think we'll even see greater success."

The chief does acknowledge the response times need to get better.

"It's just not going to be perfect," White said. "I don't think anybody would expect for us to always be perfect."

"When you dial 911 and you expect a police officer to show up, I think it's incumbent upon us we get there before Dominos gets there," Gavito said.