Recent events in Ferguson and St. Louis, Missouri, have called attention to the importance of on-the-ground smartphone videos. Civilian smartphone video was crucial to the public's understanding what was happening in the early days of the Ferguson protests, before the national media began covering the story 24/7. And among the (obviously many) differences in circumstances between the explosively controversial Mike Brown shooting in Ferguson and the fatal shooting just days later of Kajieme Powell by St. Louis police was the existence of video footage recorded by a bystander and released to the public 24 hours after the incident occurred.

Simply put, when there's video evidence showing exactly what happened, there's less room for conjecture, falsehoods, wild theories and conflicting versions of the truth from any side of the argument. Now that more than half of Americans own smartphones, according to Pew, any crime, protest, arrest or other possibly contentious public situation that involves law enforcement is increasingly likely to be video recorded by a bystander.

Of course, one expects every smartphone to have a built-in video recording app, but locally stored recordings can get lost, digitally corrupted, accidentally deleted or, in more controversial cases, purposely deleted by a police officer after seizing the phone. That's why it's important for activists, protesters and anyone else who wants to keep video evidence of a public encounter with law enforcement to literally have a backup plan. The American Civil Liberties Union's Police Tape app -- and half a dozen similar apps for iOS and Android -- provide just that, by backing up your video to the ACLU's servers.

The Police Tape app for iOS and Android is a particularly good example of police recording apps to check out because -- along with offering simple audio and video recording with the option to send the file to the cloud -- it also provides a "Know Your Rights" section that quickly and clearly explains your rights when encountering an officer in public and recording them. It also provides practical advice on how to politely assert those rights while not escalating what might already be a tense situation.

The recording feature itself is pretty bare bones, but you wouldn't expect an app made by the organization StopWatch and distributed by the ACLU's New Jersey branch to try to rival Instagram or Vine. Just hit the button, and it starts video recording. It automatically saves the video or audio file to your phone. (Android users, there's no option to save to microSD, so make sure you have enough free space on the phone.)

When you exit the app, you'll be prompted to either upload the file to the ACLU-NJ or not. If you do, it'll be stored in the advocacy group's own servers, and they'll even review the footage to see if anything happened that violated your rights.

Since "Police Tape" is an app specifically offered by the ACLU in New Jersey, it's pretty foolproof to use in that state, from a legal standpoint. However, other states have varying wiretap laws and court precedents regarding recording people without express permission, so make sure you know your local laws before doing any recording that could possibly legitimately land you in jail.

As a general rule, according to a well-sourced Reason article (which was updated for 2014 by Gizmodo), you should be able to record police in every state of the Union if you're doing it clearly and openly (not secretly), if you're located in a public space, if you're not obviously interfering with the officer's duties and you respect reasonable orders like "step back" or "stay on the other side of the street," and if they are officially performing police duties in that public space. But recording police in any less candid and public circumstances may get you into legal gray areas, depending on which state you live in.

And it's important to note that following those aforementioned rules doesn't guarantee that the police can't and won't detain or arrest you for "interfering" with police business or a similar charge -- which opens you to all the legal liabilities that go along with being taken into custody.

It also doesn't guarantee that the police might not seize your phone and try to delete your video recording. But backing up those recordings to the cloud does guarantee that your documented account of the situation won't disappear for good.

Related