"The communication and the negotiation many times in situations like this is just a time-buyer," he said. "You're buying [time] ... so that you can get more information and boost your intelligence."
Jack Cloonan, a former hostage negotiator with the FBI and an ABC News consultant, said that not knowing whether a suspect is under the influence of any drugs or prescription medication also can make the situation hard to navigate.
"It's a highly charged environment," said Cloonan. "Do we know if the person is doped up? Self-medicated? You just never know."
Suspects often want to talk to negotiators about exactly why they did what they did, Cloonan said.
"More times than not the person on the other hand is going to tell you what happened," said Cloonan. "They are going to want to explain their thinking because they're proud of what they've done. They want to be recognized."
"They will explain in some detail what their grievances are," he said. "You can elicit a lot of information by simply saying, 'What happened? People are not shy about talking."
Cloonan said hostages who have escaped the scene can be very useful to hostage negotiators.
"The hostages themselves and witnesses are absolutely critical," he said. "One thing you want to know and what these people can sometimes tell you is if the [suspect] is acting alone."
ABC News' Emily Friedman and Dan Childs contributed to this report.