TULSA, Oklahoma - We The People Oklahoma stood in front of City Hall Thursday morning calling for an investigation into this practice that they say is unethical and possibly illegal.

"What we don't want to do is have this swept under the rug," said Marq Lewis of We the People Oklahoma.

The local activist group filed a two-page formal complaint calling for change within the Tulsa Police Department after a News On 6 and The Frontier investigation revealed the internal practice of "buying rank."

In a News On 6 story last week, we explained the process where qualified officers have paid tens of thousands of dollars to higher ranking officers to retire early. In return, the eligible officer is promoted sooner.

"It's a danger to public safety if you have an officer using money to get leverage,” said Lewis. “They are the law. They are supposed to maintain the law and they are supposed to enforce the law and to enforce what's ethical on their charter."

The group’s complaint cited the city ethics code which says officials and employees cannot receive gifts that influence their duties.

In the complaint, We the People Oklahoma claims buying rank can lead to corruption, favoritism, and cronyism.

Tulsa Mayor Dewey Bartlett promises to look into it.

"We have a procedure in place where it will be evaluated, investigated, and a report issued soon," stated Bartlett.

Tulsa Police Chief Chuck Jordan told News On 6 he asked the city attorney in 2010 for a legal opinion about the practice and was told it was legal.

But city attorneys can't find any documentation of that.