Representatives from Apple, the Justice Dept., and the FBI, along with a leading academic, were called to the hearing in the wake of a legal case that erupted last month, in which a California magistrate judge compelled Apple to help the FBI unlock the iPhone used by one of the San Bernardino terrorists.
Apple refused to comply with the order, which it argued would set a "dangerous precedent," and later filed a motion to dismiss the case.
The witnesses conflicted on various points in their opening statements published Monday, but all agreed on varying degrees that the case should be decided by Congress and not the courts. FBI director James Comey, who testified before the committee but did not release an opening statement, said that the courts "cannot resolve... [the] collision between public safety and privacy."
Here are the key takeaways that you need to know:
FBI 'can't crack iPhone' without a court order
Comey told Rep. Darrell Issa (R-CA, 49th) that the FBI went "to all areas of government to see if anyone can unlock the iPhone," but was unsuccessful.
In other lines of questioning, the FBI director confirmed that the NSA, which has a history of breaking into networks and devices, was unsuccessful.
Without help from Apple, federal agents aren't ever getting into the terrorist's iPhone.
"We can get into that phone with our computing power, if [Apple] takes off the auto-erase and the delay between guesses function," he said.
One Republican lawmaker criticized the FBI for arguing that the government needs "more tools and more compulsion," but that even members of Congress "can't even see what you're already doing."
Rep. Jason Chaffetz (R-UT, 3rd) said the FBI would "routinely refuse to explain" how it uses technologies, such as stingray cell-site impersonators and zero-day exploits, leaving open the suggestion that the agency may misuse its power relating to the iPhone case.
Other nation states could have 'international implications'
The FBI director argued that there would be some "international implications" in regards to the Apple case, but was pushed further by one prominent Californian lawmaker.
"It may be that the alternative is a world where nothing is private," said Rep. Zoe Lofgren (D-CA, 19th), referencing Comey's comments.
Lofgren, a staunch privacy advocate and friend in the House of many tech companies for her district's proximity to Silicon Valley, echoed similar sentiments by her congressional colleague Sen. Ron Wyden (D-OR), a member of the Senate Intelligence Committee, who argued the Apple case could easily "snowball" around the world.
"Why in the world would our government want to give repressive regimes in Russia and China a blueprint for forcing American companies to create a backdoor?" said Wyden in comments in mid-February.
Beijing has previously pushed for legislation demanding access to encrypted systems, citing its own national security concerns. A move in that direction would be devastating for Apple, which generates accounts for almost half of its global revenue, but also other Silicon Valley companies that rely on China for large portions of its revenue.
Apple's general counsel Bruce Sewell said no other country had demanded backdoor access to its products or its customers' data. "The only place we're having this debate is in our own country," he said.
"You're not going to like what comes out of Congress"
Lawmakers are expected to file a brief in favor of Apple's case with the California court that ruled in the FBI's favor, Reuters reported on Monday.
The move sends the strongest signal yet that members of Congress may end up legislating to decide on the fate of Apple -- and similar cases -- rather than the courts. Sewell threw his weight behind that proposed effort, urging lawmakers to move on the matter, but that drew ire from one lawmaker.
Rep. Jim Sensenbrenner (R-WI, 5th), who originally helped to pen the Patriot Act in the wake of the September 11 terrorist attacks, asked if Apple had a particular bill to consider. Sewell argued that it was the FBI that brought the matter to the courts, but admitted there wasn't a bill that Apple supported.
"I can tell you you're not going to like what comes out of Congress," said Sensenbrenner. It was a subtle hint that the Justice Dept. can take a law and interpret it for its own gains, which in part led to the Wisconsin lawmaker introducing the Freedom Act last year, a counter-effort to his original bill.
Rep. John Conyers (D-MI, 13th), the ranking member of the committee, added that lawmakers should discuss possible legislative outcomes "even if the dialogue does not yield the results desired by some in the law enforcement community."
FBI "made a mistake" in initial attempt to unlock iPhone
Comey told the committee that he and others would still be testifying even if the FBI was able to get access to the device's backup stored in the cloud.
That's a reversal from a statement made by the FBI, which previously said that the password reset incident wasn't its mistake.
The terrorist's iCloud account was reset shortly after the FBI took custody of the iPhone, meaning the phone and the device couldn't talk to each other, according to Apple executives speaking to sister-site CNET. San Bernardino County's official Twitter account later announced that the county was "working cooperatively with the FBI when it reset the iCloud password at the FBI's request," pinning the blame on the federal agency.
Other snippets from the hearing:
Issa asked if the FBI asked Apple for access to its source code. Comey said it was not aware if it had. "We wouldn't be litigating if we could," said Comey.
Comey confirmed that the FBI has seen "most of the metadata" relating to the San Bernardino shooter's communications.
Conyers made a note of the timing of the court case. He said he "would be deeply disappointed if it turns out that the government is found to be exploiting a national tragedy to pursue a change in the law."
Rep. Jerry Nadler (D-NY, 10th) argued that even if Congress were to pass a law to allow device access, bad actors could still use their own encryption.
Rep. Judy Chu (D-CA, 27th) put the onus of responsibility on the FBI in the iPhone unlock case. She said that safe manufacturers "are not required to keep keys to safes or locks," therefore Apple should not be compelled to. "It's clear technology is outpacing the FBI's capabilities," she added.