Kansas City, Mo. ? Beginning next month, anyone who pleads guilty to a felony in Jackson County must surrender a DNA sample, a tactic that county prosecutor Mike Sanders believes will not just solve but also prevent crimes.

Sanders’ new policy goes beyond state law, which since 1994 has required DNA samples from people convicted in homicides, certain sex offenses and some other violent crimes.

The decision drew criticism from the American Civil Liberties Union, which says the policy constitutes a constitutional violation and an invasion of privacy. A national ACLU attorney said he knew of no other county prosecutor who had required people to surrender DNA as part of plea agreements.

The DNA samples will go into a Missouri database that authorities use to solve crimes.

“If you’re interested in prosecuting the guilty and protecting the innocent, you can’t be against this,” Sanders said.

The DNA would be used only for identification, Sanders said. DNA clears suspects when their genetic markers do not match those found at crime scenes, he said.

Sanders said he decided to take the action after the Missouri Legislature, citing the likely cost, failed this year to approve a bill drafted by his office to require DNA sampling of all convicted felons. Kansas enacted such a law last year.

The new policy is opposed by some defense lawyers and civil libertarians.

“It’s an invasion of your constitutional right not to incriminate yourself,” said Bruce Houdek, past president and board member of the Missouri Association of Criminal Defense Lawyers. “It uses the power of the office to extract something I believe is unfair.”

Jay Stanley of the ACLU in Washington, D.C., said DNA laws that took hold in states during the 1990s only for killers or sex offenders were being expanded.

“Now some states are pushing it to all arrestees,” said Stanley. A few law enforcement authorities have even suggested getting DNA from all newborns, he said.

Though the ACLU opposes Sanders’ policy, Stanley said he doubted that it could be overturned in court.

Sanders pointed to local successes of DNA evidence. Jackson County already has prosecuted about 10 murders or rapes thanks to DNA at crime scenes matching that in convict databases, he said.

Many more cases will be solved as more DNA is recorded, he said.

Across the state line, Wyandotte County Dist. Atty. Nick Tomasic said requiring DNA sampling would discourage some defendants from pleading guilty to felonies.

“What if a guy raped people five years ago? He’ll say no” to a plea agreement, Tomasic said.