Apple and the U.S. Department of Justice will argue in court Tuesday about whether a judge should require the tech giant help the FBI unlock an iPhone used by the San Bernardino, California, mass shooter.The hearing, before Magistrate Judge Sher Pym of U.S. District Court for the Central District of California, is the end result of weeks of court filings, media coverage, and often contentious debate. The case has pitted advocates of\u00a0encryption and other security measures on electronic devices against law enforcement agencies trying to fight crime and terrorism.[ ALSO: The economics of back doors ]Here are five things to remember about the hearing, scheduled to begin at 1 p.m. PDT in California.1. Apple faces an uphill climb: Pym, in mid-February, ordered the company to assist the FBI in breaking the password protections on an iPhone used by\u00a0Syed Rizwan Farook,\u00a0one of the shooters in the San Bernardino attack on Dec. 2. Apple has resisted, asking Pym to overturn her earlier order. While Pym has taken written arguments from all sides, she would have to change her mind for Apple to win in her court.2. The case doesn't stop with Pym: Whatever happens before the magistrate judge, the losing side is certain to appeal the case. That means the case could get another hearing in district court, and beyond that, appeals court, and potentially even the U.S. Supreme Court. The case touches on several important public policy issues, so the nation's highest court may be interested, some legal experts say.3. Apple has a lot of support: Even though early polling found a small majority of U.S. residents siding with the FBI, Apple enjoys strong support from the tech industry and from a vocal group of privacy and security advocates.Among the companies filing briefs in support of Apple are\u00a0Google, Microsoft, Facebook, Amazon, Cisco Systems, LinkedIn, eBay, Kickstarter and Reddit. Also supporting Apple's position are the Electronic Frontier Foundation, the Electronic Privacy Information Center, Consumer Action, the Center for Democracy and Technology, the American Civil Liberties Union, 32 law professors and 46 technologists, researchers and cryptographers.Meanwhile, digital rights group Fight for the Future says it has collected comments in support of Apple from nearly 20,000 people over the past week. The group\u00a0plans to read and display the comments outside Tuesday's hearing.4. What's the FBI's argument?\u00a0The FBI and DOJ argue they need access to the iPhone to fully investigate the Dec. 2 shootings and determine whether the suspects were working with accomplices.The FBI\u2019s request relies heavily on the\u00a0All Writs Act, a U.S. law dating back to the late 1700s, allowing courts to "issue all writs necessary or appropriate in aid of their respective jurisdictions and agreeable to the usages and principles of law."More broadly, the FBI, DOJ and President Barack Obama's administration have argued that smartphones and other devices protected by encryption shouldn't be exempt from court-ordered law enforcement searches.\u201cHere, the government has obtained a warrant to search the phone of a mass murderer, but unless this Court enforces the Order requiring Apple\u2019s assistance, the warrant will be meaningless,\u201d DOJ lawyers wrote in a\u00a0stinging rebuke\u00a0of Apple filed Feb. 19.5. What's Apple say?\u00a0The company argues Pym\u2019s order ignores several limits on the All Writs Act and is "unreasonably burdensome" by requiring Apple to create a new operating system, tying up six to 10 of its employees for up to a month.Apple has also argued that the judge's order would violate its First Amendment, free speech rights by forcing it to write new code, in essence forcing it to speak. The company also argues the order violates its due-process Fifth Amendment rights by requiring the Apple to "do the government\u2019s bidding" in a way that\u2019s burdensome and violates its "core principles."