Topeka ? A lawsuit claims a Kansas sheriff fired a detective for refusing to end an investigation into a 21-year-old man accused of sexually assaulting five women and a 13-year-old girl.

In the lawsuit filed Wednesday in U.S. District Court for Kansas, Al Dunn says Jackson County Sheriff Tim Morse pressured him to back off the investigation of Jacob Ewing of Holton. Ewing has pleaded not guilty to several charges including rape and aggravated indecent liberties with a child under the age of 14.

The federal lawsuit claims Morse pressured Dunn, a 16-year veteran, “to become associated with his political need to appease the family/friends of the subject Jacob Ewing,” court filings said.

“(Dunn) believes and expressly alleges that his speech related to the investigation of Jacob Ewing was a substantial motivating factor behind defendant Morse’s decision to suspend and then terminate him,” the lawsuit said.

Morse told The Topeka Capital-Journal the claims are “baseless” and “ludicrous,” and that his department hasn’t faced pressure to back off the investigation. He also said he wouldn’t discuss Dunn’s termination because it’s a personnel matter.

“I have no personal relationship with (Ewing’s family),” Morse said.

The lawsuit accuses Morse of violating Dunn’s rights freedom of speech, freedom to associate, due process rights and other violations. Dunn is seeking about $150,000 in lost salary and mental and emotional distress.

Morse, a Democrat is seeking re-election against Republican Robert McNicholas in the November election, according to the Jackson County elections website.

After Dunn’s termination, the Kansas Bureau of Investigation began assisting sheriff’s office. Morse said the two agencies have continued their investigation. In early September, more than a month after Dunn left the department officers served Ewing his sixth arrest warrant while he was already in the Jackson County Jail.

“(Ewing) wouldn’t be in my jail if I didn’t think there was probable cause he committed these crimes,” Morse said.