David Muir

And we're talking about boys that are 15, 16, and 17 years old.

The Austin Police Department

administered polygraph exams of both Pierce and Wellborn, but essentially they decided that any information that they had was not legitimate and that they were likely not involved in the yogurt shop murders.

And then they test Maurice Pierce's .22 and it doesn't match.

It's not the gun.

Period.

End of story.

For the families, this just added to their pain and turmoil and grief.

They were not able to get a simple, clear, direct answer about who killed their daughters.

Today, the families of the four teenage girls murdered in a Northwest Austin yogurt shop held their first joint news conference.

As police chase down every possible lead, the search for the killer or killers drags on from days to weeks and then finally to months and still nothing.

Billboards begin to go up all over Austin in a desperate effort to shake loose any clue.

On the six-month anniversary of the yogurt shop murders, people converged at the state capitol.

People were holding lighted candles.

Investigators are still no closer to cracking the case.

As hopes for an arrest begin to fade, public frustration begins to grow.

For the Austin Police Department, it continued to put a bright spotlight on their investigation.

The pressure

for them to solve this case was above and beyond any case that they've ever experienced before ever.

And I dare to say that this was the biggest case that ever happened in Ostrich's history.