Alien and Sedition Acts, in American political history were four laws passed in 1798. The Naturalization Act raising from 5 to 14 the number of years of United States residence required for naturalization was repealed in 1802. The Alien Act, empowering the president to arrest and deport any alien considered dangerous, expired in 1800. The Alien Enemies Act, which expired in 1801, provided for the arrest and deportation of subjects of foreign powers at war with the United States. The Sedition Act made it a criminal offense to print or publish false, malicious, or scandalous statements directed against the U.S. government, the president, or Congress; to foster opposition to the lawful acts of Congress; or to aid a foreign power in plotting against the United States. Although the Sedition Act enacted some reforms in the existing law of seditious libel—evidence of the truth of the alleged libel could be pleaded in justification—its penalties were severe: imprisonment for up to five years and fines up to $5,000.
The Alien and Sedition Acts were enacted by a Congress dominated by the Federalist Party and signed by President John Adams during the war crisis with France that followed publication of the XYZ letters. These documents had revealed that French officials had demanded bribes from American diplomats in Paris as a condition for negotiations to preserve the peace between the two nations.
The Naturalization and Alien Acts were aimed largely at Irish immigrants and French refugees who had participated in political activities critical of the Adams administration. The Sedition Act was an attempt to curb newspaper editors who supported the Republican Party and who, in many cases, were also immigrants and refugees. The duration of the law (until March 3, 1801) indicated that its purpose was to obstruct Republican Party activities during the presidential election of 1800. Before it expired, about 25 people were arrested and about 10 were convicted. Some of them were later pardoned.
The most prominent opponents of the Alien and Sedition Acts were the Republican Party leaders, Thomas Jefferson and James Madison. They drafted, respectively, the Kentucky and Virginia Resolutions of 1798 as part of their campaigns to protest Federal violations of civil liberties and Federal restrictions on the freedom of the press clause of the First Amendment to the U.S. Constitution. The resolutions also became important in American political history after 1830 as precedents to justify the doctrine of nullification (the principle that the states could nullify federal laws). The Alien and Sedition Acts were widely unpopular and played a major role in both the downfall of the Federalist Party and the election of Jefferson to the presidency in 1800.