Picture it..
1913. Woodrow Wilson is sworn into the office of President. The 16th Amendment becomes law. Rosa Parks is born. And, importantly for purposees of this story, somebody is smuggling jewels into the United States, evading the taxes on jewel imports.
The New York Tribune found out about the smuggling and ran a story on it. The Wilson administration wanted to prosecute the smugglers and anybody in the Customs Service who was cooperating with the smugglers. The prosecutor suspected that a Tribune employee, Burdick, paid a bribe, which was a crime, to a Customs Service official for information about the smuggling. The prosecutor wanted the identity of he Customs Service official. Burdick refused to testify, invoking his right against self-incrimination. In an attempt to force his testimony, President Wilson issued a pardon to Burdick. With no threat of prosecution for paying a bribe, Wilson thought Burdick would be forced to testify. Burdick refused to accept the pardon.
Eventually, the US Supreme Court ruled in Burdick's favor. If Burdick had been granted immunity by the prosecutor, as usually happens in this kind of case, he could have been forced to testify. But a pardon, the Court said, is different. No one is required to accept a pardon, and the acceptance of a pardon is an admission of guilt..
This brings us to the differences between legislative immunity and a pardon. They are substantial. The latter carries an imputation of guilt; acceptance a confession of it. The former has no such imputation or confession. It is tantamount to the silence of the witness. It is noncommittal. It is the unobtrusive act of the law given protection against a sinister use of his testimony, not like a pardon, requiring him to confess his guilt in order to avoid a conviction of it.
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