The Assassination of Philip Barton Key

A love triangle between a Congressman, his wife, and a U.S. Attorney turns violent when a mysterious letter is received…

February 24th, 1859 - a Thursday - was one of the last days that the United States Congress would be assembled that month. Several members were prepared to head back to their respective states and districts; but for Congressman Daniel Sickles, this was just like any other Thursday.

Sickles, a New York native and representative, lived in Washington DC with his wife, Teresa, and his daughter, Laura. He was a fair bit older than his wife - having been in his mid-30's when the two married, while she had been just 17 at the time. This caused Teresa's parents to wish against their union - citing the age gap - but the two had married in secret in September of 1852. Ever since, the two had been happily married, but a series of ups and downs would bookmark this momentous Thursday evening... with many of the downs yet to come.

Congress recessed for the night, vowing to return the next day to begin debating the usefulness of a Navy Shipyard in Sickles' district; which he was more than willing to extend Congress' stay in DC to keep. Sickles was a trusted adviser of President James Buchanan, so his voice carried a lot of weight in D.C. - and he knew it. His words of warning were not idle threats.

Sickles returned to his house that evening, the historic Ewell house, which was just up the road from the White House itself. By the time he got there, things were already loud and jubilous, with Sickles and his wife, Teresa, hosting a local newspaper publisher's wife that evening. The paper had published favorable articles about Sickles recently, and the Sickles - who hosted formal dinners every Thursday - were glad to accept the publisher's wife as their honored guest this Thursday evening.

The group would have dinner and then began heading out to a local establishment named Willard's Hotel, where they participated in their nightly "hop." This allowed those in the region to mingle and let loose just a tad, and was the perfect nightcap to the Sickles' formal dinners.

Teresa, Daniel's wife, took several guests to Willard's in their carriage; while Daniel, having spent a large part of his day sitting, decided to walk. He told his wife and guests that he would catch up, and set out to Willard's on-foot.

The carriage set off, and as Daniel prepared to leave, he was stopped ever-so-briefly by a messenger, who handed him a yellow envelope. This letter had come from an unknown sender, but Sickles thought nothing of it at the time. He tucked the envelope into his jacket pocket without a second thought, and didn't even think to ask who it had come from. He'd get to it later.

While Daniel walked to the hop, Teresa made her way into Willard's Hotel. There, she began to mingle with those in-attendance; in particular, a handsome young man named Philip Barton Key II. Key, a U.S. Attorney, was a young widower whose wife had died a few years prior. He had a reputation for being one of the most charming men in all of Washington D.C., and was a noted ladies man. Him simply speaking to Teresa - while sitting on a couch near the dance floor - stoked some whispers that something was amiss.

When Daniel Sickles arrived at the establishment, Teresa and Barton separated... perhaps hoping to avoid suspicion. But it is worth noting that Barton was a well-known friend of the Sickles family - as well as a political ally of Daniel's - so no one seemed to take this chance encounter beyond face value.

The next hour or two would pass by in a blur, and later that evening, Daniel and Teresa Sickles would return home. Teresa went upstairs to go to bed, while Daniel stepped into his study, hoping to catch up on correspondence. He thought back to the letter in his jacket pocket, which he had tucked away earlier. He just now remembered it, and decided to open up the yellow envelope.

Afterwards, he would remark that he was equally parts shocked and horrified at what he read. The letter read as follows:

"Dear Sir: With deep regret I inclose to your address the few lines but an indispendsable duty compels me so to do seeing that you are greatly imposed upon.

There is a fellow I may say for he is not a gentleman by any means by the [name] of Philip Barton Key & I believe the district attorney who rents a house of a negro man by the name of Jno. A Gray situated on 15th street between K and L streets for no other purpose than to meet your wife Mrs. Sickles.

He hangs a string out of the window as a signal to her that he is in and leaves the door unfastended and she walks in and sir I do assure you that he has as much the use of your wife as you have. With these few hints I leave the rest for you to imagine.

Most respectfully Your friend R. P. G."

It is unknown what immediate reaction Daniel Sickles had to reading this letter, but we do know that its contents began to fester inside of him; eventually consuming him. This letter would lead to one of the most sensational stories in United States history, and - ultimately - an act of violence that would unfold just a stone's throw away from the White House itself.

This is the assassination of Philip Barton Key II.

Daniel Edgar Sickles was born on October 20th, 1819, to his parents George and Susan Sickles. His father was a real estate investor - who doubled as a legal mind and politician - who urged Daniel to follow in his footsteps. Despite eventually getting there, Daniel went off the beaten path to find his own way in life.

Daniel Sickles was known for being incredibly bright and ambitious. While he eventually found his calling in legal pursuits and politics, he took a roundabout way of getting there - working a series of odd jobs such as printer - and even dropped out of college at the University of New York.

However, as a young adult, Sickles studied law under Benjamin Butler, who had been the Attorney General for Presidents Andrew Jackson and Martin Van Buren. Sickles passed the bar exam in 1843, and opened a law office of his own shortly thereafter.

From this point forward, Sickles would become increasingly involved in the political sphere, choosing to associate himself with local politicians; eventually becoming fast friends with many. He was elected to the New York State Assembly in 1846 at the youthful age of 27.

Shortly thereafter, Sickles would marry the young woman who had become the apple of his eye: a daughter of Italian immigrants, named Teresa Bagioli. At the time of their marriage, Teresa was only 17 years old, but was incredibly bright and intelligent (with many noting that she spoke at least five different languages). She would quickly become pregnant with their first and only child - a daughter named Laura - and the family became inseparable. Teresa and Laura would often follow Daniel on his political assignments, even when it led to their family temporarily moving overseas.

You see, at around the time that the Sickles married, Daniel had begun working for an established politician named James Buchanan. At the time, Buchanan was serving as the Ambassador to London (appointed by then-President Franklin Pierce), and Sickles came recommended by a mutual friend of theirs, who admired Daniel's brains and gumption. Sickles was quickly hired on as Buchanan's Secretary of Legation, and would serve directly underneath Buchanan himself.

Buchanan quickly grew to admire Daniel, calling him a "very agreeable and an able man," with "much energy of character [who] will make a favorable impression here."

Following this assignment to England, Daniel and Teresa planned to move their family to Washington D.C. Here, Daniel planned to live close to the White House, and looked for a home just down the road from his friend James Buchanan, who had become the 15th President of the United States in March of 1857.

Daniel had run for Congress upon their return, and was easily elected to the U.S. House of Representatives, where he would represent New York state in the 35th and 36th Congresses.

Over the next few years, Daniel and Teresa Sickles would cement themselves in DC culture, regularly hosting both new blood and old blood; people that were just coming to Washington, and those had grown up there. Due to this extravagant lifestyle - which they viewed as a worthy investment for their future - Daniel was often required to travel back home to New York, where he maintained his law firm. This meant that he would have to travel quite often, leaving his wife in the company of those he respected and adored...

Philip Barton Key II was the son of lawyer, author, poet, and American icon Francis Scott Key, who had cemented his own place in history decades prior with the writing of "The Star-Spangled Banner" during the British bombardment of Fort McHenry.

Born on April 5th, 1818, Barton Key (as he became known) was expected to do great things from an early age. In his youth, he was sent away to the finest boarding schools in the nation, and was pressed by his father to pursue academic achievements . Frank, his father, would pass away when Barton was just 25 years old, but left behind his entire law library in the hopes that Barton:

"... will make such use of it as will enable him to assist his younger brother and sisters and the children of his brother John."

Barton would make good on his father's wishes, and pursued a career in law. Eventually, he would be named a U.S. Attorney for the District of Columbia by President James Polk at the age of 28, eclipsing even his own father's career trajectory.

In his personal life, Barton Key had fallen in love with a woman named Ellen Swan, whose father was a popular attorney from Baltimore. The two married in 1845, and would eventually have four children. Their relationship wasn't long for this world, however, with Ellen passing away around a decade later due to health complications. This left Key widowed at an extremely early age, and he would never remarry. According to many, Ellen was his one true love, and he struggled to find love after her shocking death.

Even worse - at around this time - the current political climate was making it very unlikely that Barton would be able to retain his position as U.S. Attorney. The presidency was changing hands, and he was one of the men that was likely to lose his post due to the turnover.

So in 1857, Philip Barton Key II reached out to a potential new friend: a young Congressman named Daniel Sickles, whom he knew was close to the incoming President. Sickles interceded on his behalf, speaking to President Buchanan and allowing Key to keep his job as the U.S. Attorney for Washington DC. Sickles knew full-well that this would give him a favor to call in should the need arise, and planted the seeds for what appeared to be a healthy political alliance.

Little did Sickles know, though, that he had helped one of the most handsome and charming men in all of Washington D.C. retain not only his job, but his social standing. And in the process, he had put this man in close proximity to his wife, Teresa, who immediately became smitten with Barton.

Over the next few years, things operated rather smoothly.

Daniel Sickles was a U.S. Congressman who had the favor of the President himself, and who seemed poised to go on to bigger and better things. His name was being bandied about for all kinds of political assignments, and his name had been thrown to the top of the potential pile for Senatorial bids. There was even a non-zero chance that he might have been considered an early Presidential candidate.

Meanwhile, you had Barton Key, who was still the U.S. Attorney for the District of Columbia. He had become widely-known as a womanizer following the death of his wife, whose charm and good looks allowed him to pursue a number of romantic relationships. An acquaintance of Key's would later state that Key often bragged:

"I only need thirty-six hours with any woman to make her do what I please."

Key was often regarded as the closest thing to American royalty, due to him constantly being introduced as "the son of Francis Scott Key," the man who had literally written America's anthem.

This brings us to the evening of Thursday, February 24th, 1859.

That evening, Daniel Sickles would open up a letter which alleged that his wife of several years, Teresa, was having an affair with Barton: a man that had become a trusted political ally and friend to his family. Daniel had helped Barton keep his job by putting in a good word with President Buchanan, and in return, Barton had helped out however he could; even helping figure out real estate paperwork for when the Sickles moved to DC.

Now, it seemed like Key had overextended his hand, and had begun a romantic relationship with Teresa Sickles. There had been some whispers in the months prior, alleging that the two had been having an affair while Daniel was away on business; but Key had done his best to downplay the rumors as mere gossip. Daniel had seemed willing to believe him then.

Now, though, the excuses seemed to have fallen flat. This was no longer just a rumor passed through word-of-mouth... this was a specific claim offering up proof. The letter had been written by a mysterious individual calling themselves "R. P. G." but that identity was unknown to Sickles. He had suspicions on who this might have been, but would never know for sure.

The morning after he read this letter, Daniel Sickles began reaching out to some trusted allies of his, whom he hoped could help get to the bottom of his wife's alleged adultery. These allies began investigating the matter at-hand; primarily, the location where the alleged affair had been taking place, a house located along Washington's 15 Street.

It wasn't until that Saturday - February 26th, 1859 - that Daniel Sickles finally confronted his wife, Teresa. He demanded to know the full truth of the matter, telling Teresa that he knew all about her affair with Philip Barton Key, and wanted to know the specifics: how long it had been going on, where it had taken place, etc.

Teresa quickly confessed to the affair, and - at the wishes of her husband - wrote out the specifics in a multi-paragraph confession. This confession runs a bit long, so I won't read it, but needless to say, it went into some extensive detail which confirmed the rumors that Daniel had received in the letter.

Teresa Sickles confessed to having an affair with Barton Key, meeting him at the house in question (many times), and claimed that the affair had started the year prior, when Daniel was away in New York state on business. It had continued on until just days prior, having resulted in Teresa meeting up with Barton in the home he had rented exclusively to carry on their affair.

In this emotional confession, Teresa even admitted to carrying on the affair in the Sickles' home, in what was perhaps the most crushing blow to Daniel himself.

The signing of this letter of confession was witnessed by one of the Sickles' maids, as well as one of Teresa's closest friends and confidantes, who had happened to be their guest on this unluckiest of weekends. Following the confession, Daniel had taken Teresa's wedding ring from her, proclaiming that their marriage - as he knew it - was over.

That night, Daniel and Teresa fell asleep in separate rooms, with those inside the house recalling their sobbing carrying on until the late evening hours.

Entering Sunday, Daniel Sickles was still enraged. He now knew that the rumors surrounding his wife and Philip Barton Key were true, with whispers having followed the two for months. He had originally downplayed the gossip - believing it to be mindless chatter - but now knew that he had been played for a fool.

Now, his worry was focused less on his own personal feelings, but the opinions of others. He was sure that many others knew the truth - having observed Teresa and Barton in the year or so since their affair began - but had either been too afraid or embarrassed to tell him. He was worried that his reputation and his honor were being put on the line, and began growing emboldened to act upon this perceived dishonor.

That day, Philip Barton Key was walking towards Lafayette Square, wher ethe Sickles home was. Standing at the other end of the park, he began waving a handkerchief from a distance, hoping to attract the attention of Teresa Sickles from her 2nd story window. Little did he know that their affair was now known by Teresa's husband, who quickly saw the man - and knew what he was doing.

The next several minutes passed by in a blur, but Daniel had a friend of his run interference; he wanted to keep Key in the public square for as long as possible, as he prepared. Daniel donned a thick coat, and hidden underneath this coat were three different firearms... all of which were cocked and readied.

Sickles quickly advanced on Key moments later, who was unaware that there were now hostilities between the men. Key reached out a hand, asking a customary:

"How are you?"

As he did, however, Sickles produced a hand of his own... which was gripping a pistol. Loudly, he proclaimed:

"Key, you scoundrel, you have dishonored my house. You must die."

Barton Key barely had the chance to respond "What for?" when a gunshot shattered the relative silence of Lafayette Square.

The shot missed, but a small skirmish would ensue, with the two men hoping to gain an advantage on the other. Sickles quickly broke free, was able to reach into his coast and produced another firearm, which he unloaded in the direction of Key, who cried out:

"Don't shoot me!

"Murder! Don't murder me! Murder!"

Sickles was uncaring about the other man's pleas, and quickly advanced on his fallen rival. He hit Key once in the torso, and then once more in the head; the latter, at nearly point-blank range.

A small crowd would gather around the scene. First, they were curious onlookers, but then police and other emergency personnel. News of the event soon reached the desk of President James Buchanan himself... and soon, would be splashed across the front page of every newspaper in the country. A Congressman had just murdered - nay, assassinated - a U.S. Attorney.

Following this murder, Daniel Sickles surrendered to local police, while an autopsy of Philip Barton Key's body was performed. Prosecutors began working on what would be the most highly-publicized trial in American history up to this point.

Daniel had confessed to the crime and calmly surrendered to police, with the pistol balls in Key's body later being confirmed to have come from his pistols. There was no sense in denying the crime, so... Sickles took an alternative route to prove his innocence.

Acquiring some of the top legal minds in Washington at the time, Daniel Sickles would become the first person in American history to use the defense of temporary insanity, claiming that his wife's infidelity had driven him insane.

This defense was aided by his counsel's clever use of the media in the trial, which publicized details of the affair between the victim and Daniel's wife, Teresa. This included her entire confession letter, which had been ruled inadmissible in court. This led to the public overwhelmingly supporting Sickles through the trial, with numerous publications praising him as a hero who somehow defended his honor in murdering a romantic rival.

In many ways, the trial itself almost seems like a harbinger of things to come; with it being most easily compared to the O.J. Simpson trial from over a century later. It had that much of an effect on the nation itself, and was more highly-publicized than anything else at the time.

After a multi-week trial, Daniel Sickles would be acquitted for the murder of Philip Barton Key II. The media blitz and claims of temporary insanity had paid off; which - while it was the first time such a defense had worked, would not nearly be the last.

Almost immediately, Sickles began to withdraw from public life, but refused to resign from Congress. He simply chose not to engage himself in public life any more, relocating his family back to New York and leaving behind the D.C. social life that his wife and he had dominated for several months.

Daniel would reunite with his wife, Teresa, eventually choosing to forgive her for her infidelity; an act which, shockingly, earned him more ire in the public consciousness than the murder of her lover had. However, the relationship between the two would be forever fractured, with the two remaining estranged over the next several years.

In 1861 - just about two years after his acquittal - the U.S. Civil War would begin, and Sickles went on to become a highly-ranked officer in the Union Army. Despite some high profile mishaps which he was undoubtedly responsible for - including a noticeable gaff at the Battle of Gettysburg - Sickles would eventually be awarded the U.S. Medal of Honor for his actions during the war. He lost a leg, and was permanently handicapped from this point forward.

In 1867, Teresa Sickles finally succumbed to tuberculosis, which was just one of the many ailments she had been suffering from in the months prior. She left behind her own family, as well as her only child: Laura, her daughter who was just coming of age.

Following the Civil War, Daniel Sickles would spend the next several decades working in a number of positions and posts: the U.S. Minister to Spain, the Sheriff of New York County, and even becoming a U.S. Congressman again in 1893 (when he was elected to the 53rd Congress). During this time, he remarried and had two more children.

In May of 1914, Daniel Edgar Sickles passed away in New York City. He was 94 years old.

Even though 160 years have passed since the murder of Philip Barton Key II, and the last involved individuals passed away over a century ago, there remain some unanswered questions about this dramatic scandal. There are a number of ends that have yet to be tied up; namely, the identity of the person who essentially started this entire story... "R. P. G.", the mysterious letter-writer who tipped off Daniel Sickles to his wife's affair.

It is not believed that Sickles himself ever learned the identity of this individual, and it is not believed that the initials R.P.G. were known to him at the time. This name would be brought up in the highly-publicized murder trial, with the original letter even being read in court and introduced to the public record. In fact, during the trial, Daniel Sickles' defense placed ads in newspapers, asking for this alleged witness to come forward with their information.

During the trial, a witness named William Rapley was called to the stand, and claimed that on Thursday, February 24th - the same day that Daniel Sickles had received his anonymous letter - his eventual victim, Barton Key, had received a similar letter in a yellow envelope. This did not seem to be a simple coincidence, and led many to believe that this might have been a calculated campaign carried out by someone.

That is not all, though.

On April 21st, 1859 - the 16th day of the trial - a letter was received by one of the jurors. This letter was regarded by the overseeing judge as:

"... an impertinent, improper, and unwonted interference with a court of justice."

Like the original R.P.G. letter, its author was unknown, but seemed to express knowledge of the case itself. It called back to the original mystique of the letter that had started this entire ordeal, and seemed particularly defamatory towards Daniel Sickles himself.

This second letter seemed to share the same handwriting as the original R.P.G. letter, which lawyers on both sides agreed upon. The handwriting was unique, and the writer had seemingly made no attempt to disguise their handwriting.

There exist numerous possibilities as to whom had written these letters; perhaps political schemers, hoping to get either Daniel Sickles or Barton Key out of their way. Or even romantic rivals, with Teresa having many known admirers and Barton having broken many hearts himself. It was possible that R.P.G. could have been someone trying to break up the affair for the purposes of keeping either Teresa or Barton all for themselves, but without knowing the identity of this mysterious letter-writer, their motivations remain a mystery today.

There continue to exist many unanswered questions in this story. In particular, who was R.P.G. and what was their intention in starting this feud between Daniel Sickles and Barton Key? Did they intend for this story to end in violence, or did they have some other aspiration?

It seems like we'll never know the answer to this question. But Chris DeRose, who just recently published a book about this case - titled "Star Spangled Scandal" - believes that this story helped bring the entire genre of true crime to popularity. He also believes that this story had a huge impact upon America itself, despite the story being overshadowed by the explosive events of the Civil War just two years later.

Because we don't know who wrote the original letter to Daniel Sickles (or what their intentions were), this story - the assassination of Philip Barton Key II - remains unresolved.


Episode Information

Episode Information

Written, hosted, and produced by Micheal Whelan

Special thanks to Chris DeRose, author of the book "Star Spangled Scandal," for agreeing to speak to me and for all of his assistance in making this episode happen. Please make sure to grab a copy of his book online or at your nearest bookstore. You can learn more by checking out his publisher's page at

Producers: Maggyjames, Ben Krokum, Roberta Janson, Quil Carter, Peggy Belarde, Matthew Brock, Laura Hannan, Astrid Kneier, Evan White, Katherine Vatalaro, Damion Moore, Amy Hampton Miller, Timothy Stratton, Scott Meesey, Steven Wilson, Sara Willemsen, Scott Patzold, Kathy Marie, Marie Vanglund, and Lori Rodriguez

Published on June 30th, 2019

Music Credits

Rest You Sleeping Giant - "Leaving For Chicago"

Lee Rosevere - "Breathing"

Alan Spiljak - "Harmony"

Graham Bole - "Away An Wash Yer Hauns Ya Clatty Article"

noiseonport - "spectre"

Alan Spiljak - "Empty Days"

Mystery Mammal - "Leer"

Other music created & composed by Ailsa Traves

Sources and further reading

Chris DeRose - “Star Spangled Scandal”

Wikipedia - Daniel Sickles

Wikipedia - Teresa Bagioli Sickles

Wikipedia - Philip Barton Key II

The Sickles Saga