19-year-old college student Jennifer Cusworth was found dead in a ditch in rural Kelowna in 1993. Neil George Snelson is on trial for her first degree murder. (RCMP)

A father of four insists he had no involvement in the murder of a 19-year-old Kelowna college student almost two decades ago.

Neil Snelson was charged with the first degree murder of Jennifer Cusworth in October 2009 after the case sat cold for 16 years.

Cusworth was last seen alive at a downtown house party in October 1993. Two days later, her body was found face-down in a ditch along Swamp Road in rural Kelowna.

When he took the stand on Tuesday, Snelson admitted he was at the same house party as Cusworth the night she disappeared.

He told the jury he had been drinking heavily that night, and admitted having sex with a woman from the party in the front seat of his truck.

He testified that while he initially told police he didn't know who that woman was, he now thinks it might have been Cusworth.

When asked by defence lawyer Wade Jensen if he murdered Jennifer Cusworth, Snelson replied, "No," in a calm, quiet voice and said he didn't know who did.

When asked if he took part in Cusworth's murder, Snelson replied, "No, sir. I did not."

DNA evidence a match

On Monday, a forensics expert for the Crown testified there is overwhelming DNA evidence linking Snelson and Cusworth.

Dr. Norma Szakacs told the jury that semen samples taken from Cusworth's body match a DNA sample RCMP took from Snelson in 2009.

She said the odds that the semen belonged to someone other than Snelson is one in 36 trillion.

Cusworth's elderly parents, Jean and Terry Cusworth, are in Kelowna for the duration of the trial but have said they will not comment until the trial is over.

With files from the CBC's Brady Strachan