This is the first post in a two-part series looking at the contentious but increasingly relevant issue of recording police interactions. In this series, we offer up some case-study examples of situations where surveillance cameras have been used as a force for good.

We've often commented on the double-edged nature of persistent surveillance. On the one hand, constant surveillance can lead to various privacy and civil liberties abuses. But as the following stories show, widespread adoption of surveillance cameras by both law enforcement actors and civilians can also help hold both parties accountable.

This is especially true with police dashboard or wearable video cameras, currently being used by law enforcement agencies around the world, which are designed to record most interactions between police and citizens.

"If police departments have good policies regarding the footage that bans surreptitious recording, [and] includes an exclusionary remedy when the camera’s selectively turned off by officers at the wrong time, et cetera, they can be great,” Kade Crockford of the ACLU Massachusetts previously told Ars when discussing wearable video camera technologies for officers. "If used correctly, cameras can be beneficial to reduce police brutality and can aid accurate record-keeping. But we’re waiting to see how they’re implemented.”

The following examples are situations where police officers have been caught lying or acting improperly after video footage surfaced showing their apparent malfeasance.

Car Wrecked

Background: Wisconsin resident Tanya Weyker was involved in a serious car crash with a Milwaukee police officer’s vehicle in February of last year that broke her neck and wrecked her car. Weyker was facing drunken driving charges stemming solely from the arresting officer's testimony at the time of the crash.

What the cops said: The arresting officer said that he had obeyed traffic laws and blamed the crash on Weyker. The officer claimed that Weyker appeared to be intoxicated at the time—even though he could not administer field sobriety tests due to the serious nature of her injuries.

What the accused argued: Weyker countered that the officer had caused the accident when he rolled through a stop sign and “T-boned” her car. She also claimed that she had not been intoxicated at the time of the accident.

What the video showed: Footage from a nearby airport surveillance camera showed that the officer had caused the crash when he failed to stop at a stop sign and struck Weyker's car, just as she had stated. What’s more, the results of drug and alcohol tests administered at the hospital became available and confirmed Weyker’s sobriety at the time of the crash.

Suppressed evidence

Background: What would have otherwise been an unremarkable evidence-suppression hearing for a drug stop took an unexpected turn when dashboard camera footage from a police cruiser was dramatically introduced in court. The emergence of the footage after the officers had testified led to what the ABA Journal called a "Perry Mason moment," whereby information is unexpectedly introduced that changes the court's perception of the situation dramatically.

What the cops said: At the hearing, the five officers testified that they arrested 23-year-old Joseph Sperling only after smelling marijuana during a routine traffic stop, searching his car, and then finding nearly a pound of marijuana lying on the back seat.

What the accused argued: Sperling countered that the officers who had testified against him in open court had lied about the sequence of events on the day in question. Instead, Sperling claimed that the search occurred after he had already been removed from his car and placed under arrest. As a result, he argued that the search was improper and the evidence obtained should be suppressed in accordance with the "exclusionary rule," whereby unlawfully obtained evidence (in most circumstances) cannot be presented in court.

What the video showed: The police video presented at trial directly contradicted the officers' sworn testimony, and showed that the search only occurred after Sperling was taken from his car and handcuffed. As a result of the introduction of the video evidence, Cook County Circuit Judge Catherine Haberkorn suppressed the seized marijuana. Prosecutors soon thereafter dismissed Sperling's felony charges. "All five officers were later stripped of their police powers and put on desk duty pending internal investigations. And the state's attorney's office is looking into possible criminal violations," according to Sally Day, spokeswoman at the state attorney's office, as reported by the Chicago Tribune.

Massaged truth

Background: After a police unit raided a tanning salon and massage parlor on the north side of Chicago last summer during a prostitution investigation, things got ugly quickly when the officers detained a frightened store manager named Jianqing Klyzek.

What the cops said: After the incident, officers pursued a felony indictment against Klyzek on battery charges, claiming that she bit and scratched them as well as resisted arrest when they tried to detain her.

What the accused argued: Klyzek's attorney, Torreya Hamilton, argued that her client, a licensed masseuse and naturalized US citizen, was entirely innocent and had been mistreated by the police. “She’s never been arrested before, and she hadn’t done anything wrong," Hamilton stated.

What the video showed: Surveillance footage from the parlor showed that during the raid and while Klyzek sat on the floor in handcuffs, an officer proceeded to strike her from behind, while another threatened to use an electronic taser gun on her “10 f**king times.” “You’re not f**king American! I’ll put you in a UPS box and send you back to wherever the f**k you came from,” an officer shouted at Klyzek. The prosecutor's office, upon reviewing the footage for the first time after the grand jury investigation had begun, then dropped all charges against Klyzek.

Brutalized

Background: After police responded to a domestic dispute call at the home of 30-year-old New Jersey resident named Marcus Jeter that led to the arrest of neither Jeter nor his girlfriend, Jeter left home in his SUV. Officers then proceeded to follow Jeter's vehicle and to pull him over on the Garden State Parkway, where the situation turned from bad to worse for Jeter, reports New York Daily News.

What the cops said: The cops said that they struck Jeter because he was eluding police pursuit, had resisted arrest, and had assaulted the officers when they tried to detain him. Jeter faced a multitude of criminal charges and an initial plea offer of up to five years in prison as a result of the officers' testimony, reports New York Daily News.

What the accused argued: "When [the cops] were behind me with their lights on, I pulled right over" Jeter described in a TV interview with WABC. "I wasn't trying to escape." Instead Jeter described how the cops acted violently and aggressively towards him, despite his cooperation. "The next thing I know, as [one cop] is coming around the car, the glass gets busted up and all the glass goes in my face. My hands are up. As soon as he opens the door, one of the officers just reached in and punched me in the face." He then described how the officers pried him from the car, threw him to the ground and proceeded to brutally beat him.

What the video showed: The two videos (recorded from two police cruisers) corroborated Jeter's story. They show one of the officer slam into Jeter's car with the police cruiser, and another smash his window and rip him from his car all while Jeter's hands are in the air. "Stop resisting! Stop trying to take my f**king gun!," one officer shouts at Jeter while he appears to do nothing to signify that he is engaging in the actions the officer described. Jeter then responds "I've done nothing wrong," as he is being thrown face-first into the cement. One officer then retorts, "Shut the F**k up," before they pin him against the patrol car and again strike him in the back of the head.

Aftermath: "I was going to be doing jail...The first plea [offer] was 5 years," Jeter told WABC. Instead, once the tape from the second police cruiser emerged, showing the officer's car violently striking Jeter's vehicle and clearly contradicting the police officers' statements, the prosecutor's office dropped all charges against Jeter. While the officers were not initially charged with any crimes for their treatment of Jeter, Bloomfield's Mayor Michael Venezia wrote on his Facebook page that he was "outraged" by this "police cover-up."

"This behavior is unacceptable," he wrote. "I have contacted the Essex County Prosecutor's Office to request an investigation of our police department's internal affairs division."

Totalled

Background: A few days after installing a Timetec Roadhawk Dashcam in his car, a Dealspin writer "Ted" was involved in a serious car crash with a US border patrol vehicle at a busy intersection.

What the cops said: The driver of the van approached Ted after the accident screaming "Didn't you see the light" and accused him of running a red light and causing the accident. In the police report taken at the scene, the border patrol agents reported that their “van was westbound on Rockaway making a left turn southbound onto Farmers Blvd states thought [sic] all Eastbound traffic stopped for vehicle’s turret lights and red light at intersection.“

What the accused argued: In his confused post-accident delirium, Ted said he was unsure what had happened.

What the video showed: The video showed that when Ted entered the intersection the light was green and that the van's driver had caused the accident by turning left as Ted lawfully entered the intersection. "If not for my Dashcam," Ted explained, "I would have been made to feel guilty for causing this accident, and my insurance would have found me at fault. With this video, it is clear as day... that I was just driving along with the flow of traffic, and the van made an absolutely illegal turn!"

In the second post in this series, we'll look at situations where officers were vindicated after individuals falsely reported their interactions with the police and the tapes showed the officers were in the right.