A judge on Wednesday refused to toss out the criminal case against a doctor accused of violating Kansas' late-term abortion law, saying a former prosecutor's conduct in the case didn't warrant such action.

Sedgwick County District Judge Clark Owens also denied a defense request to throw out evidence in the case against Dr. George Tiller of Wichita because of the conduct of former prosecutor Phill Kline.

Tiller, one of a few U.S. physicians performing late-term abortions, is to go on trial March 16 on 19 misdemeanor charges alleging he failed to obtain a second opinion for some late-term abortions from an independent physician, as required by Kansas law.

Tiller's lawyers contended that Kline and his subordinates conducted an unconstitutionally selective investigation of Tiller, engaged in "outrageous governmental conduct" and illegally gathered evidence. Kline, an anti-abortion Republican, began investigating abortion clinics when he served as Kansas attorney general from 2003 to 2007.

"While Phill Kline testified that he would like for all abortions to be outlawed, his investigations made no attempts to prevent lawful abortions from being performed in the State of Kansas," Owens wrote.

Tiller's attorneys, who contend their client is innocent, said they were disappointed with the ruling, which they can't appeal until after trial, in the event he is convicted.

"While we had hoped that the taxpayers might be spared the expensive security and litigation of this hyper-technical political trial, we certainly respect the court's right to disagree with our analysis of the facts and the law," his attorneys said in a statement.

Ashley Anstaett, spokeswoman for Kansas Attorney General Steve Six, said in an e-mail that prosecutors are moving forward with the case.

Kline, who now works at Liberty University in Lynchburg, Va., did not immediately return a message left on his cell phone.

His attorney, Caleb Stegall, said the ruling was a vindication of the investigation conducted by the attorney general's office.

"No investigation and set of prosecutions in Kansas has ever been subject to the level and intensity of scrutiny that this investigation has borne," Stegall said.

In his ruling, Owens noted that after Kline left the attorney general's office, Democrat and abortion-rights supporter Paul Morrison took over the case. It was Morrison who filed the charges against Tiller.

"Once the investigation was assumed by Attorney General Paul Morrison, the acts of Phill Kline could not have tainted the investigation and prosecution of this case," Owens wrote.

The judge noted that the Kansas Supreme Court, which criticized Kline in December for his conduct in handling copies of medical records from the abortion clinics, found Kline had broken no law. He said the high court's criticism didn't mean the case against Tiller should be thrown out.

"His procedures have certainly been questioned by the Kansas Supreme Court, but his conduct in the investigation does not merit the sanction of the dismissal of the charges or suppression of evidence," Owens wrote.