Wichita ? Although black motorists are more likely to be stopped at night in Kansas’ largest city, a researcher studying new police data says it doesn’t prove racial profiling.

“I think it has to do with who’s out and who’s not out,” said Brian Withrow, a Wichita State University professor.

The new numbers, released by police this month, show that police stop blacks at night at a rate more than 2 1/2 times their percentage of the population.

“It suggests to me that driving patterns may be different with respect to racial groups,” Withrow said.

One national expert on racial profiling, University of Toledo (Ohio) Law School professor David Harris, said it’s logical to assume there is a larger percentage of black drivers on the roads at night.

During the daytime, Harris said, many cities see their streets fill with white suburban commuters but most leave the city limits before sundown.

Census figures suggest that could be true for Wichita.

Within the city limits, there were 6.2 white residents to every black resident when the 2000 Census was conducted. For the area outside the city limits, the ratio was 45.6 to 1.

Also, Police Chief Norman Williams said, more officers are on the streets at night because that’s when most of the crime occurs. He said some of those who come into contact with police after dark probably are witnesses to crimes that have occurred in black neighborhoods.

In preparing a report that was released in April, Withrow analyzed data from 37,454 police contacts from January to July 2001. For most of last year, Wichita officers were required to fill out forms noting the race of the people they contacted.

The study found that blacks were involved in 20.7 percent of the contacts. Census figures, meanwhile, show that blacks made up 11.4 percent of the city’s population.

Withrow noted the disparity in his report, but he said the numbers did not prove that racial profiling exists.

The data released last week involves 48,564 police contacts that occurred from January through early October of 2001. Of those contacts, 20.8 percent involved blacks.

But the data also show that the odds of a black resident being stopped increased after dark. Between 8 p.m. and 5 a.m., 26 percent of all police contacts involved blacks, and about 40 percent of all police contacts occurred during those hours.