What did the Supreme Court actually decide?
The Court separated two tests that the government had treated as the same. Ms. Cardoza-Fonseca, from Nicaragua, sought asylum and withholding of deportation, relying largely on what had happened to her politically active brother, who had been tortured and imprisoned. The immigration judge applied a more-likely-than-not test to both requests. The Supreme Court ruled on March 9, 1987 that this was wrong for asylum. A person can fear an event with good reason when there is less than a 50% chance of it, and the opinion rejected the idea that a 10% chance of being shot or tortured means there is no well-founded fear. That ruling did not grant her asylum; it fixed the standard. Next step: if a form, an officer or an advisor tells you that you must prove you will be persecuted, ask which protection they mean, because for asylum that is the wrong test.
What is the test today?
Under 8 C.F.R. § 1208.13(b)(2), you have a well-founded fear if you fear persecution on a protected ground, there is a reasonable possibility of suffering it if you return, and you are unable or unwilling to return because of that fear. You need not prove you would be singled out if you show a pattern or practice of persecuting people like you. Against you, though, the fear fails if you could reasonably relocate within your country. The burden is yours under INA § 208, and a protected ground must be at least one central reason for the harm, so a lower chance does not fix a weak link. Next step: write a dated list of threats and incidents, then ask a lawyer to compare it with country conditions evidence for your group, not only with your own story.
How do asylum and withholding differ?
Think of them as an easier door with a guard and a harder door without one. Asylum uses the lower well-founded-fear test, but it is discretionary: a judge or officer may still say no. Withholding of removal under INA § 241 requires proof that harm is more likely than not, a greater than 50% chance, but the Court described it as mandatory once proven. Protection under the Convention Against Torture uses the same more-likely-than-not level for torture and needs no protected ground. Timing differs too: asylum generally has a one-year filing deadline, so a late applicant may be left with the harder tests. Next step: Form I-589 is the application for asylum and withholding, so ask your lawyer to request every protection that fits, and make sure you understand all of it before you sign.
Where does this standard not help?
It lowers only the likelihood you must show. It does not change the need for a protected ground or for government involvement or failure to protect. If private actors are the threat, Matter of S-S-F-M- now makes that much harder. It also leaves all the bars to asylum in place. Discretion can go against you as well, because the Court noted that an eligible person still faces a discretionary decision. Our individual hearing guide explains how a contested hearing runs. Do not plead a percentage, because the regulation asks for a reasonable possibility. Next step: ask your lawyer to show why your facts meet each element, one at a time, and treat 10% as an explanation of the law, not a target for your evidence.
How do I prove a well-founded fear?
Your own testimony may be enough, but only if it is credible, persuasive and specific, and the law lets a judge require corroboration you can reasonably obtain. That is a warning, not a comfort: you should assume you need more than your word. Gather what you can: summonses, medical records, messages, news reports, and statements from people who saw what happened. If an item is impossible to get, record why. Keep your account consistent across every form and interview, because mistakes are costly. In court, the defensive asylum process sets the order of events; before USCIS, see affirmative asylum. Asylum fees and deadlines are explained on our Form I-589 page. Do not sign a sworn statement you cannot read: have it translated and read back. To go through your evidence before you file, see our asylum page.