One can be forgiven for assuming that a fatal stabbing on a notorious block of San Francisco's Sixth Street was a dispute between a couple of the area's more downtrodden residents. But as details emerge in a homicide from earlier this month, the truth is far stranger.

You might recall the brief tale: at around 10 p.m. on Thursday, September 3, witnesses say a 31-year-old man and a 61-year-old man were involved in a "physical altercation," which escalated to the point that younger man stabbed the older man in the torso. The victim, SF resident James Thomas, died at the scene.

The stabbing went down on Sixth Street between Market Street and Mission Street, just steps from SFPD's Central Market Safety Hub.

Now here's where the tale takes a turn from typical police blotter fare into something less expected: The suspects in the crime are an attorney and an intern with an area tenants' rights group, both of whom were caught on tape during the homicide.

Bay City News reports that 31-year-old Carlos Alejandro Argueta, a staff attorney with the Eviction Defense Collaborative and 21-year-old EDC intern Pascal Krummenacher had gone out drinking that night to celebrate Krummenacher's final day of his internship.

The EDC provides "emergency legal services " to help "low-income tenants respond to eviction lawsuits," according to their website.

According to Assistant District Attorney John Ullom, the duo was so wasted that they had gotten “thrown out of a bar” that night, and Krummenacher's defense attorney Lewis Romero concurs, saying they were “quite inebriated."

The men were headed back to the EDC's offices at the corner of Sixth and Market Streets when video evidence viewed by the Examiner...

...appears to show Krummenacher and Argueta, who is wearing a black messenger bag, walking on Sixth Street toward Market Street when four men confront them.

The video shows Argueta being pushed against a car. The four men then walk south on Sixth Street with Argueta holding his hands up alongside them. His bag is no longer on his back, but now appears to be in possession of the man later identified as Thomas.

When the men appear again on the surveillance footage, they are walking toward Market Street with the defendants following. This time, Krummenacher’s carrying a reddish bag in his hand.

According to prosecutors, BCN reports, "Krummenacher saw Thomas pushing a shopping cart with a messenger bag that he mistakenly thought was Argueta’s missing bag and took it...Thomas took the bag back, but Argueta then took the bag again, gave it to Krummenacher and allegedly stabbed Thomas twice during a struggle."

The video shows "Argueta stick the older man with a knife. The man later identified as Thomas drips blood on the sidewalk, stumbles and falls over." Thomas died at San Francisco General Hospital later that night.

As an angry crowd gathered, Argueta retreated into nearby Tu Lan restaurant, where he later spoke with police. According to Romero, "a drunken Krummenacher hopped on a BART train, passed out and woke up at the end of the line."

While Krummenacher, who lives in London, was arrested the next day, the Ex reports that the "District Attorney’s Office initially declined to press charges against Argueta, but he was charged Monday when prosecutors said they had sufficient evidence." He's expected to turn himself in today.

Both men are charged with murder, counts of second-degree robbery, and receiving stolen property. Argueta also faces two counts of assault with a deadly weapon.

According to Argueta's LinkedIn profile, he's been with the EDC since June of this year, where he says he uses his "legal skills to ensure the 'little guy' has a fighting chance and is treated justly."

Krummenacher has been released on $1 million bail, and is wearing a GPS ankle bracelet to quash any impulses to flee. According to Roberto Evangelista, Argueta's public defender, Argueta will be arraigned Friday, where he faces a bail amount that he "will not likely be able to afford."

Previously: SF's 32nd Homicide For 2015: Stabbing Near SFPD Substation