WEST HAVEN, Conn. (WTNH) — From the Wood Chipper murder case, to the OJ Simpson trial and hundreds in between, Dr. Henry Lee has worked on some of the world’s most high profile investigations.

“In 80’s and 90’s almost every major case happening in this country and some even around the world, we assisted them,” said Lee, Professor and Associate Vice President at the University of New Haven.

That includes a double murder in Beverly Hills that rocked the 1990’s.

A pair of privileged and wealthy brothers.

Their parents were gunned down in the living room of their Beverly Hills mansion.

Dr. Henry Lee was called in to examine the forensic evidence.

“Two opposite cases in the beginning, one was the intruder theory, maybe some mafia connection. The killing was pretty brutal. Almost like an execution style,” said Lee.

It was so violent, many including police didn’t originally suspect Lyle or Erik Menendez could have played a role.

It was Dr. Henry Lee’s job to set emotion aside, and study the actual evidence.

In this case it was the lack of evidence.

“As a forensic scientist we usually don’t consider the human factor, we let the evidence speak for itself.

That’s the beauty of forensic evidence, evidence can tell.

“At the initial evaluation in this case we did not find any sign of an intrusion by somebody else,” said Lee.

Soon, the pieces of the puzzle came together, revealing the Menendez brothers horrific plot to kill their parents.

“Most of the time if the individual try to cover up – the more you left more clue,” said Lee.

A cover up that led to a confession and ultimately, life behind bars for Lyle and Erik Menendez.

The brothers are serving in separate prisons.