A courtroom sketch shows Ahmed Abu Khattala, third from right, listening to an interpreter through earphones in federal court in Washington on Oct. 2. (Dana Verkouteren/AP)

Ahmed Abu Khattala's militia hit men formed "the tip of the spear" in 2012 attacks that killed Ambassador J. Christopher Stevens and three other Americans at U.S. facilities in Benghazi, Libya, prosecutors said at the end of a seven-week terrorism trial.

Assistant Federal Public Defender Michelle Peterson countered that the government played to emotions of jurors in Washington, accusing her client of "hating America" to try to divert them from holes in the prosecution.

A federal jury of 12, all residents of the nation's capital, is set to begin deliberations Monday over the fate of the man charged with helping orchestrate attacks that stretched from the night of Sept. 11, 2012, until nearly dawn the next day at a U.S. diplomatic mission and nearby CIA base.

The trial tested the ability of the civilian courts — rather than military commissions — to prosecute foreign terrorism suspects captured overseas and interrogated in a two-step system in which one team of questioners extracts useful intelligence and is followed by a separate FBI team that collects evidence for trial under legal safeguards for a defendant.

The trial also moved the inquiry of what happened in Benghazi from the political realm, where the attacks drove Republicans claim of a Democratic coverup during the 2016 presidential contest, and into a courthouse to weigh evidence gathered from a years' long investigation.

Ambassador J. Christopher Stevens shown in Benghazi in an April 11, 2011, file photo. (Ben Curtis/AP)

Abu Khattala, 46, has pleaded not guilty and faces life in prison if convicted of 18 charges, including murder, attempted murder and conspiracy to support terrorism.

The trial featured dramatic testimony from surviving State Department and CIA operators, some of them taking the stand under fake names and disguised in wigs and mustaches to protect their identities. Prosecutors also relied heavily on surveillance video taken by overhead drones and diplomatic compound cameras, and cellphone records the government obtained from Libyan authorities.

Key evidence, however, came from three, paid Libyan informants all testifying under pseudonyms, including one who received $7 million for luring Abu Khattala to his June 2014 capture by U.S. Special Operations forces after he had posed for months as a financial supporter of Abu Khattala to gather information.

Abu Khattala was seized and taken to a Navy warship for questioning and transport to the United States.

Months of sealed litigation and negotiations preceded the trial over tens of thousands of pages of classified documents about the case that the government turned over to the defense. The sides reached agreements on what information was relevant to the charges against Abu Khattala before dozens of declassified summaries were read into the record in open court in lieu of live testimony from classified sources.

Marines carry caskets during the return to the U.S. of the remains of the four Americans killed in the Benghazi attacks. (JEWEL SAMAD/AFP/GETTY IMAGES)

In impassioned closing arguments, Assistant U.S. Attorney Julieanne Himelstein on Thursday called the victims "our American sons," and Abu Khattala a "stone cold terrorist" so committed to a "fanatical agenda" of establishing a strict Islamist state in Libya that he set in motion the violent attacks.

"You will not hear the defendant was involved in the initial charge on the [U.S. diplomatic] mission. You will not hear that he lit the match. . . . You will not hear that he fired the mortar. It does not matter," Assistant U.S. Attorney Michael C. DiLorenzo argued. "Because a person is equally guilty as an individual who lit the match or fired a mortar, if they are a co-conspirator or an aider and abettor."

He said "indisputable" records linking the times of calls on Abu Khattala's phone and surveillance video from the diplomatic mission showed he was at least a key plotter in the attack. And one Libyan witness said he was present in 2013 when Abu Khattala allegedly confessed, "I intended then to kill everybody [all the Americans] there, even those who were at the airport. " It was not clear if that meant U.S. security reinforcements temporarily stranded at the airport the night of the attacks or survivors who went there in the morning to evacuate.

DiLorenzo said, "There may be other participants, but they are acting in concert with his (Abu Khattala's) men."

The defense team challenged a prosecution that Peterson, in her closings, said hinged on testimony from Libyan informants whose character and motivation were suspect.

The three Benghazi witnesses — a military intelligence commander, militia security official and businessman who each got at least $200,000 in expenses for their assistance to the government and temporary or permanent U.S. residency for some family members — testified that they saw or heard Abu Khattala take steps to plan or carry out the attacks. Peterson called them — in order — a man caught willing to lie directly under oath, a "con man" who hid the extent and nature of his other contacts with his secret American handlers and Abu Khattala, and a "$7 million man" paid for his story, the largest payment disclosed.

She said demonizing Abu Khattala had been a core strategy by prosecutors. "They want you to hate him. That's what this case has been about. They want you to hate him enough to disregard holes in the evidence," Peterson said.

U.S. District Judge Christopher R. Cooper released the jury after closings to return Monday to start deliberating.

Jurors were selected for the trial that began Oct. 2 from more than 125 District residents who answered 28 pages of questions probing their political views, including whether they believed Democratic presidential nominee Hillary Clinton, secretary of state at the time of the Benghazi attacks, contributed to them, and whether the U.S. government acts fairly toward mostly Muslim countries, or aggressively enough to fight terrorism.

Killed in the attacks were Stevens and State Department information technology aide Sean Smith, who both died of smoke inhalation after their villa at the diplomatic compound was set on fire after 9:45 p.m. Sept. 11; and ex-Navy SEALs Tyrone S. Woods and Glen Doherty, who died in a precision mortar strike before dawn Sept. 12 defending a nearby CIA annex where compound survivors had retreated.

DiLorenzo told jurors that by law Abu Khattala — code-named "Greenbrier River" by the U.S. military after an inconclusive early battle in West Virginia in the Civil War — was guilty of any crime that was a "foreseeable consequence" of the one he conspired to commit. That crime, they alleged, was to use violence to drive out what Abu Khattala saw as a U.S. spying presence in his native city.

FBI lead case agent Michael Clarke testified that over days of shipboard questioning, Abu Khattala, who was a former auto mechanic and political prisoner of dictator Moammar Gaddafi, identified several men as members of an extremist Islamic brigade known as Ubaydah ibn al Jarrah that he helped found at the start of the Libyan revolution to establish sharia law.

The brigade was part of a larger group, Ansar al-Sharia, that the U.S. government designated a terrorist organization in 2014 and held responsible for the attacks.

At least eight of Abu Khattala's militia were caught on diplomatic compound surveillance video the night of the attacks, and calls were placed between Abu Khattala's phone and several of the men's at that time.

Surveillance video played at trial showed some of those men armed, one carrying a fuel can that prosecutors contend was used to ignite diplomatic vehicles, and another a looted map that prosecutors said showed the secret CIA annex's location not far from the diplomatic compound.

Clarke testified that Abu Khattala's statements made on the warship shifted, but that he had identified the man seen carrying the map as the person Abu Khattala rode with to and from the diplomatic compound the night of the attack.

The man, Mustafa al-Imam, was captured by the U.S. military on Oct. 29 for prosecution in Washington, the day before Clarke testified that Abu Khattala had implicated him.

DiLorenzo also urged jurors to remember a surveillance image of a man with a pistol, whom Libyan witnesses had identified as one of Abu Khattala's loyal foot soldiers, entering the diplomatic compound a minute after the attack began, and calling Abu Khattala four minutes later, according to phone records.

"This man, a member of his 'hit squad,' is this a coincidence? Guilt by association? That's ridiculous," DiLorenzo said in closing arguments, characterizing defense claims that Abu Khattala was merely a bystander.

At 10:20 p.m., as Stevens and Smith were "likely taking their last breaths," DiLorenzo summarized to jurors, Abu Khattala also called the head of a Benghazi joint security operations center, who testified Abu Khattala told him to "withdraw your men" so the attack could be completed. "That is aiding and abetting," the prosecutor said.

Peterson said the purported identifications of militia members, phone numbers provided to prosecutors, and accounts of any intent or planning by Abu Khattala all came from the three witnesses she said "had axes to grind."

Although they testified they heard Abu Khattala say he was planning the attack or saw him stockpiling weapons beforehand, Peterson said, two of the witnesses withheld or misstated to jurors their dealings with secret U.S. military handlers. They were not forthright, she said, about compensation they sought and received, and gave shifting accounts implicating Abu Khattala. The operations center witness also covered up his business dealings with Abu Khattala after the attacks, Peterson said.

The third Libyan witness, who had testified under the name of Ali Majrisi and said he had heard Abu Khattala claim he wanted to kill more Americans in the attacks, also had rejected a $1 million payment as "insultingly low" before offering to kill Abu Khattala himself and eventually receiving $7 million for his help in the investigation.

"If you are willing to get rid of someone by yourself, physically killing them, is it that much of a stretch to say you'd be willing to lie for them?" Peterson asked jurors.

She also raised whether there could be errors in the government's account of what Abu Khattala said at sea because his statements were made through an translator without a lawyer present and not recorded on audio or video. Likewise, she told jurors, the three Libyan witnesses' interactions with their classified U.S. handlers apart from the FBI had not been fully disclosed to the defense.

"This really is house of cards," Peterson said. Without the three, she said, "you don't have identifications of people they [prosecutors] say are co-conspirators. You don't get preplanning. You don't get anyone who met with Abu Khattala. Their case rises and falls on the credibility of those three people."