Oh yeah, roommates can be a lot of trouble — especially if you have too many of them.

As the pace of rental season in Lawrence picks up, city leaders are working to remind potential renters of a city law that prohibits more than three unrelated people from living in a single-family home.

“This is an ordinance that can affect you in a different way than a lot of ordinances,” said Brian Jimen-ez, the city’s code en-forcement manager. “If you violate this ordinance, we can force you to move.”

And despite a popular perception to the contrary, Jimenez said the city does enforce the law and require some renters to move before their leases are up. Since 2007, the city has investigated 52 complaints of housing occupancy violations. Jimenez said that in about 50 percent to 60 percent of those cases, the city found too many people living at a residence.

Although the city occasionally will let the violation persist if there are only a few weeks left on a lease, increasingly the city is forcing at least one of the tenants to move.

“We have compassion as much as the next person regarding that, but most of the time we really don’t have any other option,” Jimenez said.

The ordinance came about after residents in several neighborhoods surrounding Kansas University complained that single-family homes were being converted to rentals that often housed large numbers of people. The rental houses often created problems in terms of neighborhood parking, trash and noise issues, residents said.

Neighborhood leaders said the city has made some progress on the issue, but there are still concerns about landlords who ignore the law.

“I would call it mixed success,” said Tom Harper, a member of the Centennial Neighborhood Association. “There’s some landlords who I think just ignore it. When they do, it seems like all the city can do is send them a letter.”

Proving violations in court has been difficult for the city. Jimenez said most of the cases involving people being forced to move have come about after residents or the landlords admitted that they were unaware of the law and then voluntary took steps to comply. Jimenez said the city has not taken a case to court in recent memory.

“Our goal is always voluntary compliance,” he said.

The city did take a case to Municipal Court in 2003, but lost after the judge said the city did not meet a high enough standard of proof. Simply showing evidence that there are frequently more than three cars parked at a residence, for example, is not enough to gain a conviction, the case found.

But Jimenez said the city won’t hesitate to take a case to court if prosecutors have enough evidence. He said, though, the city is hoping to increase awareness of the ordinance in order to prevent violations from occurring.