Topeka ? A law expanding the collection of DNA samples in criminal investigations will be “huge” in helping law enforcement agencies catch predators, the father of a murdered Johnson County woman said Thursday.

Roger Kemp, of Leawood, came to the Statehouse for a brief ceremony marking the law’s approval. Gov. Kathleen Sebelius re-enacted her signing of the bill, which occurred earlier this month.

Kemp’s interest in such legislation stems from the June 2002 death of his daughter, Ali, a 19-year-old Kansas State University student. He found her body in the pump room of a Leawood pool where she worked, and 30-year-old Benjamin Appleby faces a November trial on charges of first-degree murder and attempted rape.

“The citizens of the state of Kansas will be so impressed with the impact that this makes in getting these predators off the streets,” Kemp said after the ceremony. “It’s a huge bill.”

Starting Jan. 1, DNA samples must be collected from any adult arrested or juvenile taken into custody for a violent felony, such as murder or rape. Starting in July 2008, samples will be taken in all felony cases. Currently, DNA samples are not collected until after someone is convicted of a felony.

The delayed starting date will permit the Kansas Bureau of Investigation to upgrade its DNA testing laboratory.

Backers of the legislation believe law enforcement agencies will collect an additional 12,000 samples each year, making it more likely they’ll find matches with evidence in unsolved cases.

“Using the technology that we now have just makes sense,” Sebelius said. “It’s been out there, but we just haven’t made the best use of it.”

Kemp said rapists and some other offenders often aren’t arrested until they’ve committed numerous crimes.

“They’re getting smarter all the time in what they do to try to cover up their crimes, so we have to get smart in using DNA,” he said.

Joining Sebelius and Kemp for the ceremony were several Johnson County law enforcement officials and Rep. Pat Colloton, R-Leawood, who sponsored the measure.

California, Florida, Louisiana, Texas and Virginia already take DNA samples along with fingerprints at the time of arrest. The Kansas law contemplates that samples would be taken by wiping a cotton swab inside the mouth.

The sample would be analyzed by the KBI to come up with a DNA profile. Supporters of the law say while the 14 chromosomes used to construct a profile don’t contain personal information, they are enough to make a match with another sample.

If charges are dismissed, a person is acquitted or a conviction is expunged, the person could ask the KBI to destroy the sample, but the DNA record would remain in the database like a fingerprint.