Law enforcement representatives from eight states and several Lawrence police officers wrapped up a three-day seminar on homicide investigations Wednesday.

This is the seventh year the seminar was hosted by the Lawrence Police Department and led by Vernon Geberth, a consultant and retired New York City police commander, respectfully known as “Mr. Murder.”

“It’s all about investigation and proper collecting of evidence,” said Mike Byrn, a Lawrence police officer who attended the seminar in 2003. “If you get it right the first time, you won’t have to backtrack.”

The 86 officers, who came from as far away as Tennessee, each paid $430 to attend the conference, which was held at the Marriott SpringHill Suites downtown.

Each day of the conference centered on a different theme of homicide investigation: sex-related homicides, investigative analysis through profiling and DNA, DNA cases and suicide.

“Each day has a different theme, but it starts off with the mechanics of death investigation,” Geberth said.

Actual cases from around the country were used as teaching points for the officers to analyze.

“It’s a lot of information,” said Anthony Brixius, one of seven Lawrence officers at the seminar. “But, (it’s) a lot of great information you can go back to.”