As Philando Castile lay dying in a blood-soaked T-shirt inches away, his girlfriend grabbed her cellphone, flipped on Facebook Live and invited millions to watch the aftermath of an officer-involved shooting in Falcon Heights Wednesday night.

In real time, viewers hear Castile groan quietly. The view shifts up to telephone poles while police put the girlfriend on the ground. "Police shot him for no apparent reason, no reason at all," she broadcasts news to the foward-facing camera.

The Falcon Heights shooting has pushed Facebook live back in the news after the video, which appeared on a Facebook page belonging to Lavish Reynolds, went viral.

Live video's popularity has surged recently as people share and, some would say, overshade the best, worst and most banal moments of their lives. Although livestreaming video isn't new, the addition of Facebook Live has launched it into the mainstream. Now anyone with a smartphone can broadcast in real-time.

"It's a powerful way to communicate because there's no way to know what is going to happen next or whether something might go wrong," said Shayla Stern, senior digital strategist at Fast Horse, a Minneapolis marketing agency. "You can't look away from a compelling live video."

With new, easy-to-use platforms and apps, a recent crop of livestreaming videos is shining a spotlight on the positive and negative realities of real-time video technology.

In May, "Chewbacca Mom" got her 15 minutes of fame after hundreds of thousands of people shared the feel-good Facebook Live video of her laughing hysterically while wearing a plastic Wookiee mask. And a week earlier, strangers watched in helpless horror as a 19-year-old French woman used Periscope, a live video streaming app, to broadcast her suicide.

Livestreaming also arms citizen journalists with a tool to share raw, uncut and unprocessed video of major news events. For instance, within 12 hours of the grand jury announcement in Ferguson, Mo., livestreamers using UStream and LiveStream racked up 4.8 million views. And, in June, when the GOP-controlled chamber shut off C-SPAN as House Democrats protested for tighter gun laws, representatives turned to Periscope and Facebook Live.

This new human experience raises questions about privacy, ethics and intimacy online. Many are asking: "Just because we can live stream, does it mean we should?"

Livestreaming gives viewers a chance to be a fly on the wall at events they would traditionally need an invitation to.

"Livestreaming allows audiences to feel that they are experiencing events live and unfiltered, in front of their eyes," said Valerie Belair-Gagnon, an incoming assistant professor at the University of Minnesota, who will teach a class on new media and culture. "It is also powerful because it has the potential to reach certain groups of people with specific interests, share content and interact with each other."

But the very things that make livestreaming video attractive are what make it difficult to filter the bad from the good. Lives are always on display — and it's not always pretty. In the weeks since Facebook Live launched to the masses, the tool has been used to stream a suicide, a rape and a standoff with police.

"The dark side of livestreaming is that everyone can record anything and start broadcasting," said Jen Jamar, co-organizer of the Minneapolis-St. Paul chapter of Social Media Breakfast. "You not only have to worry about someone 'snapping' you at an inopportune moment in a picture; now they might capture you on live video saying or doing something that's out of context."

Chewbacca Mom had the laugh heard around the world, driving 50 million views in less than 24 hours and earning her the title of having the most viewed Facebook Live video of all time.

"To put that into context, 58,000 people went to the Beyoncé concert at TCF Bank Stadium recently, fewer than 10 million people watched the Billboard Music Awards, 17 million watched the last game of the World Series last fall and 34 million watched the Oscars," Swan said.

It's clear there are many questions about the ethical issues around privacy, safety and intellectual property with livestreamed video. For example, fans can live stream the Twins game and the Kenny Chesney concert — but should they?

"We should be talking about what is fair game for livestreaming," Fast Horse's Stern said. "There are a lot of ethical — and potentially legal — ramifications to livestreaming events that one person perceives to be private and another sees as public. We've been struggling with this issue in terms of the photos we post to social media, but live video complicates it even further."

Staff writer Danielle Fox contributed to this report.