In Sunderland v. United States, 1924, the Supreme Court examined whether a man could be convicted for using the U.S. mail system to defraud people by selling them worthless stock in his company. The defendant, Mr. Sunderland, had been sending out letters claiming that his oil company was about to strike it rich and urging people to buy shares before prices skyrocketed. However, there was no evidence of any oil on his property and he knew this fact when he sent the letters. The court ruled against Sunderland stating that even though some recipients may have not believed him or were not actually harmed financially because they didn't invest in his scheme; still it constituted fraud as per law since he knowingly misrepresented facts with an intent to deceive others for personal gain through mails which is illegal under federal laws governing mail frauds. This case thus established a precedent where actual harm or successful deception isn't necessary for conviction but mere act of attempting such deceitful conduct can lead one guilty under US Mail Fraud Statutes.

In the dissenting opinion for Sunderland v. United States, Justice McReynolds disagreed with the majority's decision to uphold a conviction based on evidence obtained through wiretapping. He argued that such methods were an invasion of privacy and violated the Fourth Amendment's protection against unreasonable searches and seizures. According to him, allowing this type of evidence would set a dangerous precedent where law enforcement could freely intrude upon private communications without any legal constraints or oversight. Furthermore, he contended that it was not within Congress' power to authorize such invasions of privacy in pursuit of criminal investigations as it contradicted constitutional protections afforded to citizens.