AUSTIN -

The final hours of Texas' special legislative session descended into chaos overnight as hundreds of protesters yelled to drown out the vote on a tough abortion restrictions bill.

To make matters worse, the timing of the vote as it was recorded on the Legislature's computer system changed right before people's eyes.

Here is how the confusion played out.

WHAT WAS THE DEADLINE TO PASS THE BILL?

Lt. Gov. David Dewhurst had until 11:59 Tuesday to pass Senate Bill 5, an omnibus abortion bill that was widely expected to shut down 37 out of 42 existing abortion clinics.

More than 400 opponents of the bill packed the Senate gallery to watch Sen. Wendy Davis, D-Fort Worth, attempt to filibuster it for nearly 11 hours until the end of the special session.

At about 11:45 p.m., Republican Sen. Robert Duncan was presiding over the Senate and using all of his authority to stop Davis while ignoring Democrats who were trying to use parliamentary rules to stall the vote.

That's when the crowd erupted in cheers, claps and shouts of "Shame!"

WHAT TIME DID THE VOTE HAPPEN?

Time ticked on until some clocks and mobile phones showed midnight.

Just as the mood in the gallery began to shift from anger to celebration, Lt. Gov. David Dewhurst called all of the senators to the front podium to register their votes.

He ignored Democrats who held up their phones, declaring that it was past midnight and that the session had expired.

Republican lawmakers voted anyway and said that the vote was valid because they had started at 11:59 p.m.

The votes were tallied into a computer system operated by the secretary of the senate.

WHY WAS THERE CONFUSION ABOUT THE VOTE?

Some reporters, including those working for The Associated Press, checked the computer system to see what day the votes were registered.

When the votes first appeared, the date next to them read "6/26/2013."

Moments later other reporters opened the same record and the date read "6/25/2013."

A reporter for The AP videoed his computer screen while refreshing the page, capturing the date changing from Wednesday to Tuesday.

The date of the vote had changed.

Democratic senators protested. Senate officials refused to answer questions about the change.

Sen. Chuy Hinojosa of McAllen produced two computer-generated print-outs of the vote tally -- one time-stamped Wednesday and the other dated Tuesday.

Sen. Carlos Uresti, D-San Antonio, checked the official journal clerk's handwritten log, and it showed the vote took place at 12:02 a.m. Wednesday.

HOW WAS THE BILL DECLARED DEAD?

Armed with that evidence, the entire Senate met behind closed doors with Dewhurst.

He emerged minutes later and tersely declared that while the vote was valid, the protesters had kept him from signing the bill in the presence of the Senate, and therefore, the bill had not been finalized. He said the vote stood but that the bill was dead.

He then hinted that Gov. Rick Perry would call another special session to pass the bill, saying, "See you soon."