Final answer:
Jurisdiction in internet transactions is not solely determined by the defendant conducting substantial business online; other factors also influence this. Amazon may support tax regulations that apply universally to create a fair market competition. Jurisdiction rules are defined by legal documents such as the Constitution and the Federal Judiciary Act.
Step-by-step explanation:
In a case involving internet transactions, the statement that jurisdiction is proper only when the defendant conducts substantial business in the jurisdiction online is false. Jurisdiction can be established in a variety of ways, not solely on the substantiality of online business activities. Factors such as the nature of the activity, the defendant's interaction with the jurisdiction, and the location of potential harms may also play a role. For instance, Amazon.com may support the Marketplace Fairness Act because it levels the playing field against competitors who avoid collecting taxes, thus posing no disadvantage to Amazon which already has a significant physical presence and infrastructure capable of handling complex tax collection.
Expression on the Internet presents unique challenges, and the Supreme Court utilizes a case-by-case approach that evolves as new cases arise. Overall, jurisdiction issues are guided by the Constitution, the Federal Judiciary Act, and subsequent amendments and court interpretations. For example, Section 2 Clause 1 of the Constitution defines the jurisdiction of Federal Courts that include cases involving federal law and interstate disputes.