Forensic system, forensic method, and forensic program

A forensic method for acquiring digital information recorded in a plurality of computers or a server and analyzing the acquired digital information, comprising:

• a step of registering a keyword for determining by a user whether a plurality of pieces of document information included in the digital information is related to a lawsuit, through a computer;
• a step of retrieving the keyword registered from the document information, through the computer;
• a step of extracting a sentence including the retrieved keyword from the document information, through the computer;
• a step of classifying the extracted document information based on the determination result for each determination result, and analyzing and selecting the keyword that appears commonly in the classified document information;
• a step of calculating a score indicating a degree of relevance to the lawsuit based on a feature value extracted from the sentence extracted, through the computer;
• and
• a step of changing a degree of highlighting of the sentence according to the score, through the computer,
• wherein the degree of relevance is assigned to the keyword using a document information group for which it is determined by the user that the document information group is related to a lawsuit in the past;
• wherein the database registers the keyword when the degree of relevance exceeds a predetermined threshold value;
• and
• wherein the feature value is extracted based on an appearance frequency or an amount of transmission information related to the keyword.

A non-transitory computer-readable storage medium that stores forensic program instructions executable by at least one processor for acquiring digital information recorded in a plurality of computers or a server and analyzing the acquired digital information, the program allowing the at least one processor to execute functions comprising:

• registering a keyword for determining by a user whether a plurality of pieces of document information included in the digital information is related to a lawsuit;
• retrieving the keyword registered from the document information;
• extracting a sentence including the retrieved keyword from the document information;
• classifying the extracted document information based on the determination result for each determination result, and analyzing and selecting the keyword that appears commonly in the classified document information;
• calculating a score indicating a degree of relevance to the lawsuit based on a feature value extracted from the sentence extracted;
• and
• changing a degree of highlighting of the sentence according to the score,
• wherein the degree of relevance is assigned to the keyword using a document information group for which it is determined by the user that the document information group is related to a lawsuit in the past;
• wherein the database registers the keyword when the degree of relevance exceeds a predetermined threshold value;
• and
• wherein the feature value is extracted based on an appearance frequency or an amount of transmission information related to the keyword.