Patent Grant
7387244
Not Applicable.
Not Applicable.
1. Field of the Invention
The present invention relates generally to voting systems, and more particularly to an electronic voting system in which a voter verifiable audit log is printed in real-time as actions are taken at a voting terminal.
2. Description of Related Art
In recent years, electronic voting systems have been widely used in elections throughout the world. Typically, an electronic voting system includes multiple voting stations each of which comprises a direct recording electronic (DRE) voting terminal. In operation, a voter selects his/her votes via a touch screen or other input device of the voting terminal. Once the voter casts his/her ballot, the voter's selection of votes are stored in the memory of the voting terminal and electronically tabulated with the vote selections of other voters. Upon poll closing, the vote totals are downloaded from the memory of the voting terminal for final tabulation with the vote totals from other voting terminals.
One issue that has been raised by computer experts with respect to electronic voting systems is that there is no paper record of the voter's selection of votes. As such, many voters are skeptical of the integrity of the election process and believe that their electronic votes may not be counted correctly. In an attempt to resolve this issue, electronic voting systems have been developed in which the voter's selection of votes are printed on either a paper ballot or a paper receipt that may be examined by the voter and/or used for auditing purposes.
In a “paper ballot” type of electronic voting system (an example of which is disclosed in U.S. Pat. No. 6,769,613), each voting station includes a voting terminal with a printer that prints a paper ballot in accordance with the voter's selection of votes. The paper ballot is provided to the voter, whereby the voter has an opportunity to examine the paper ballot for correctness with regard to his/her selection of votes. If the voter observes that the paper ballot correctly represents his/her selection of votes, he/she submits the paper ballot for final tabulation by a tabulating machine. If not, the paper ballot is destroyed and the voter is directed to another voting station to repeat the voting process.
Alternatively, the voter may insert the paper ballot into a ballot scanning machine connected to the voting terminal. If the scanned paper ballot is identical to the selection of votes stored in the memory of the voting terminal, the ballot scanning machine imprints the paper ballot with a validation code and the selection of votes are permanently stored in the memory of the voting terminal. The paper ballot is then returned to the voter who submits the paper ballot for final tabulation by a tabulating machine. If, however, the scanned paper ballot is not identical to the selection of votes stored in the memory of the voting terminal, the ballot scanning machine invalidates the paper ballot and the selection of votes are erased from the memory of the voting terminal. The paper ballot is then destroyed and the voter is directed to another voting station to repeat the voting process.
In a “paper receipt” type of electronic voting system, each voting station includes a voting terminal with an associated printer. After all of the votes have been selected, a summary page listing the voter's selection of votes is displayed on the voting terminal for review by the voter. In addition, the printer prints a paper receipt with a summary of the voter's selection of votes. The paper receipt is not provided to the voter, but is instead retained behind a protective window that allows the voter to examine the paper receipt for correctness with regard to his/her selection of votes. If the voter observes that the paper receipt correctly represents his/her selection of votes, he/she then casts his/her ballot by pressing a “cast ballot” button, whereby the paper receipt may be cut by a paper cutter and dropped into a locked ballot box associated with the voting terminal. If the voter changes his/her mind after reviewing the paper receipt, the voter may reject (i.e., cancel) the ballot and the paper receipt will be marked as “rejected.” The voter may reject the ballot up to two times, just as is regulated with a standard paper ballot.
One problem with the electronic voting systems described above is that they do not track all of the actions taken at the voting terminal. Rather, the paper ballot/paper receipt merely includes a summary of the voter's final selection of votes. As such, auditing the paper ballots would not uncover vote tabulation errors caused by poll worker actions taken at the voting terminal (e.g., in cases where poll workers mistakenly input actual vote selections into the voting terminal because they are not familiar with or trained properly on the voting terminal). In addition, the paper ballot/paper receipt does not include every action taken by the voter during the voting process.
Another problem with some of these electronic voting systems is that the paper receipt must be cut before it is dropped from the voting terminal into a locked ballot box. Thus, the voting terminal must include a paper cutter for cutting the paper receipt, which adds to the complexity and cost of the system. Also, the individual paper receipts are difficult to assemble for recount purposes. In addition, the large amount of storage space required to store the individual paper receipts is similar to that required for mechanical voting systems using standard paper ballots.
Yet another problem with some of these electronic voting systems is that the use of the voting terminal is more complex than “paperless” electronic voting systems. In some systems, the voter must examine the paper ballot and, if acceptable, submit the paper ballot for final tabulation by a tabulating machine. In other systems, the voter must insert the paper ballot into a ballot scanning machine and, if validated, submit the paper ballot for final tabulation by a tabulating machine. In yet other systems, the voter must compare the results of two different methods of display for the ballot (i.e., the paper receipt vs. the summary page displayed on the voting terminal). As a result, the voting terminal must display additional voting instructions and/or instruction screens. Also, the voter's ability to reject a ballot causes the waste of paper. In addition, the voter must perform additional steps and/or spend an increased amount of time in the voting booth (e.g., reviewing the printed summary of vote selections). Furthermore, poll workers must be trained on the use of the voting systems so as to be able to provide adequate voter assistance.
The present invention is directed to a voting system that includes one or more voting stations located within a voting precinct. Each of the voting station(s) comprises a voting terminal and an associated printer that is operable to print all of the actions taken at the voting terminal on a printable medium to thereby create a printed audit log for the voting terminal. These actions may include poll worker actions (such as poll opening, poll closing, screen calibration, time reset, report printed, PEB activation, PEB deactivation, supervisory ballot cast, and supervisory ballot cancelled) and voter actions (such as ballot selection, ballot de-selection, and ballot cast). Preferably, the audit log is created in real-time as the poll worker actions and the voter actions are taken at the voting terminal.
In an exemplary embodiment, the printable medium comprises a continuous paper roll on which is printed all of the actions taken at the voting terminal between poll opening and poll closing. Preferably, the printable medium is secured within a locked housing such that the audit log is inaccessible to a voter using the voting terminal. However, the locked housing includes a display window that enables the voter to review a portion of the audit log associated with the voter in order to verify the correctness of the voter actions printed on the printable medium.
In the exemplary embodiment, the printer is also operable to print a plurality of voter bar codes on the printable medium. Each of the voter bar codes contains information corresponding to a ballot cast by a voter at the voting terminal, and is preferably printed on the printable medium proximate the printed voter actions for that voter. A commercially available bar code reader is also provided to scan the voter bar codes printed on the printable medium. Importantly, the bar code reader operates independently of the voting terminal so as to enable an independent comparison of the voter bar codes with the voter actions printed on the printable medium for auditing purposes.
The printer is further operable to print a voting terminal bar code on the printable medium. The voting terminal bar code contains information corresponding to the vote totals of all ballots cast by the voters at the voting terminal, and is preferably printed at the terminal end of the printable medium so that it may be easily scanned by the bar code reader. The bar code reader can thus be used to scan the voting terminal bar codes of all of the voting terminals in the voting precinct.
Finally, the voting system also includes a computer that may be connected to the bar code reader so as to download the vote totals for all of the voting terminals located in the voting precinct. The computer is programmed to accumulate these vote totals to thereby generate vote totals for the entire voting precinct. As with the bar code reader, the computer operates independently of the voting terminal so as to provide an independent verification of the vote totals for the voting precinct.
The present invention has several advantages over the prior art. For example, the voting system tracks all of the actions taken at the voting terminal, including both poll worker actions and voter actions, to thereby increase the audit capabilities of the voting terminal. Also, the configuration of the printable medium (e.g., a continuous paper roll) does not require a paper cutter and reduces the amount of paper jams due to more consistent feeding of paper from the paper roll. The paper roll may also be easily fed into a high-speed reader for recount purposes. Also, the paper roll requires a minimal amount of storage space.
In addition, the voting system does not require the voter to take any additional action with respect to the printed audit log such that the use of the voting terminal is similar to that of “paperless” voting terminals. As such, the voting terminal may display a reduced number of voter instructions that will likely result in the voter spending less time in the voting booth. Furthermore, the amount of poll worker training is reduced, as is the amount of time that a poll worker may need to spend with voter assistance. Of course, other advantages of the invention will be apparent to one skilled in the art.
The present invention is directed to a voting system and method with a voter verifiable real-time audit log. In accordance with the invention, all of the actions taken at a voting terminal are printed on a printable medium in real-time so as to create a printed audit log for the voting terminal. These actions may include both poll worker actions and voter actions taken at the voting terminal. A voter is able to review a portion of the printed audit log associated with the voter in order to verify the correctness of the voter actions printed on the printable medium. As such, the printed audit log may be used for both auditing purposes and voter verification.
Referring now to
Voting system 10 also includes a plurality of voting precincts 20a-20f. Although six voting precincts have been shown in
Referring to
Voting stations 26a-26d each include a direct recording electronic (DRE) voting terminal 28a-28d and an audit log printer 30a-30d. Voting terminals 28a-28d each include a PEB reader/writer for reading information from and writing information to various PEBs (as will be described in greater detail hereinbelow with reference to
Referring to
PEB reader/writer 32 of voting terminal 28a is operable to read information from and write information to various PEBs, such as a master PEB, a supervisor PEB and/or a voter PEB. The configuration of PEB reader/writer 32 is described in greater detail in U.S. Pat. No. 5,583,329 assigned to the assignee of the present application, which is incorporated herein by reference. In the exemplary embodiment, there are two possible modes of activation for voting terminal 28a—poll worker activation mode and voter activation mode.
In poll worker activation mode, a poll worker activates voting terminal 28a by inserting a supervisor PEB into PEB reader/writer 32. Upon activation, the ballot data transferred from the master PEB to voting terminal 28a (described above) is displayed on display 34 of voting terminal 28a.
By contrast, in voter activation mode, a poll worker activates a voter PEB at a supervisor terminal (not shown) by writing an activation security code to the voter PEB. The poll worker provides the voter PEB to the voter who proceeds to voting terminal 28a and inserts the voter PEB into PEB reader/writer 32. PEB reader/writer 32 reads the activation security code from the voter PEB, whereby the ballot data is displayed on display 34 of voting terminal 28a. After the voter has completed the voting process, PEB reader/writer 32 writes a deactivation security code to the voter PEB so that it cannot be used again by subsequent voters until the voter PEB is again reactivated by a poll worker at the supervisor terminal.
Display 34 of voting terminal 28a is operable to display the ballot data for voting precinct 20a. In the illustrated embodiment, display 34 comprises a liquid crystal display (LCD) configured as a touch screen display so that a voter may select candidates and/or positions on referendums by merely touching the appropriate locations on display 34 with either a finger or a computer pen (not shown). Alternatively, if display 34 is not configured as a touch screen display, an array of switches may be included as part of voting terminal 28a for allowing the input of voter selections. Display 34 may also comprise a cathode ray tube (CRT) display configured as a touch screen display located external to voting terminal 28a. In such a configuration, the display would be connected to voting terminal 28a through a dedicated I/O connector of voting terminal 28a. Of course, other types of displays are also possible.
The internal computing system of voting terminal 28a is surrounded and protected by a sealed housing 36. The internal computing system includes a processor and various types of memory, as is known in the art. Preferably, the processor comprises a suitable microprocessor having sufficient processing capability and speed for operating voting terminal 28a. The memory may include any type of memory that is suitable for storing the ballot data, an electronic audit log, vote totals, and other information necessary for the operation of voting terminal 28a. In the exemplary embodiment, the memory comprises flash memory, EEPROMs, and a compact flash memory device or other removable data storage system. It will be seen that the compact flash memory device stores a back-up copy of the electronic audit log and is removed from voting terminal 28a after the election for transport to election headquarters 14.
Referring still to
In the exemplary embodiment, the printable medium comprises a continuous paper roll on which is printed all of the actions taken at the voting terminal between poll opening and poll closing. Preferably, the paper roll is sealed prior to election day so that votes may not be pre-printed on the paper roll. As can be seen in
Locked housing 38 includes a display window 40 that enables a voter to review a portion of the audit log associated with the voter. As such, the voter may verify the correctness of the descriptions printed on the audit log in real-time as he/she enters his/her selection of votes (although the voter is not required to review the audit log during the voting process). A magnifier may optionally be provided to assist the voter in reviewing the audit log. Of course, it should be understood that the size and configuration of display window 40 may vary between different voting terminals.
Audit log printer 30a is also operable to print a plurality of two-dimensional (2D) voter bar codes on the paper roll. Each of the voter bar codes contains information corresponding to a ballot cast by a voter at voting terminal 28a (e.g., the final vote selections for that voter). Preferably, each of the voter bar codes is printed on the paper roll proximate the printed voter actions for that voter. In the exemplary embodiment, each of the voter bar codes is of a standard ASCII format that may be scanned by a commercially available 2D bar code reader. Thus, the scanned information from the voter bar codes may be randomly compared against the voter actions printed on the audit log for auditing purposes.
In addition, audit log printer 30a is operable to print a vote summary on the paper roll that includes a 2D voting terminal bar code. The voting terminal bar code may contain the serial number of the voting terminal, the total ballots cast on the voting terminal, and the vote totals of each candidate and/or referendum issue on the ballot of the voting terminal. Preferably, the voting terminal bar code is printed at the terminal end of the paper roll so that it may be easily scanned after the election is over. In the exemplary embodiment, the voting terminal bar code is of a standard ASCII format so that it may be scanned by a commercially available bar code reader for verification purposes (as described further below with reference to
While audit log printer 30a is illustrated in
Referring to the flow charts of
Next, in step 54, a voter is authorized to vote by an appropriate election official, whereby the voter proceeds to voting terminal 28a. In step 56, voting terminal 28a is activated by inserting either a supervisor PEB or a voter PEB into PEB reader/writer 32 (as described above). In response, audit log printer 30a prints a description of the action on the audit log in step 58 (e.g., “PEB activation”). Then, in step 60, the ballot data (i.e., the various candidates and referendum issues to be voted on) are displayed on display 34. In response, audit log printer 30a prints a description of the action on the audit log in step 62 (e.g., “ballot displayed”).
In step 64, the voter selects his/her votes by touching the appropriate locations on the touch screen of display 34. In response, audit log printer 30a prints a description of each action on the audit log in step 66 (e.g., “Governor: select candidate A”; Governor: de-select candidate A”, Governor: select candidate B”, etc.). In step 68, after all of the votes have been selected, a summary page may be displayed on display 34 for review by the voter. This summary page includes a summary of each of the selected candidates/referendum positions, as well as a summary of the under-voted contests. In response, audit log printer 30a prints a description of the action on the audit log in step 70 (e.g., “summary page selected”). Preferably, a summary of the voter's final selection of votes is not printed on the audit log, as the voter has already had an opportunity to review the description of each individual vote selection in real-time as it is printed on the audit log.
In step 72, once the voter verifies that the selected votes are correct, the voter touches a “vote” button and the selected votes are stored in the memory of voting terminal 28a. In response, audit log printer 30a prints a description of the action on the audit log in step 74 (e.g., “ballot cast”). In addition, audit log printer 30a prints a voter bar code on the audit log in step 76. It should be understood that steps 54-76 are repeated for each voter.
Upon poll closing in step 78, the poll worker inserts the master PEB into PEB reader/writer 32, whereby the vote totals for voting terminal 28a are transferred from the memory of voting terminal 28 to the master PEB and accumulated with the vote totals for any other voting terminals in voting precinct 20a that have already been closed with the master PEB. In response, audit log printer 30a prints a description of the action on the audit log in step 80 (e.g., “vote totals transferred to PEB”). Then, audit log printer 30a prints the terminal report on the audit log in step 82, which includes the vote summary and voting terminal bar code for voting terminal 28a.
It should be understood that the operation of voting terminal 28a and audit log printer 30a as described in steps 50-82 is merely an exemplary method and that other methods of operation are within the scope of the present invention.
Referring to
If voting terminal 102 is the last voting terminal in the voting precinct to be closed, the poll worker disconnects audit log printer 104 from voting terminal 102 and connects a report printer 114 to voting terminal 102. At this point, the master PEB inserted into the PEB reader/writer of voting terminal 102 contains the accumulated vote totals for all of the voting terminals in the voting precinct. The poll worker is then able to print a precinct report 116 to report printer 114 based on the vote totals contained within the master PEB. The poll worker may then report the “unofficial” election results for the voting precinct to the election headquarters, either by electronically transmitting the information stored on the master PEB to the election headquarters and/or by physically transporting the master PEB to the election headquarters.
Upon poll closing, the poll worker removes the compact flash memory device containing the electronic audit log 118 from voting terminal 102 and physically transports the compact flash memory device (along with the master PEB and precinct report 116) to the election headquarters. The election headquarters utilizes a central software program and printer 120 to download the data from electronic audit log 118 and generate a printed audit log 122. In addition, software program and printer 120 are used to analyze the data downloaded from the electronic audit logs of all of the voting terminals in the voting precinct to thereby generate a precinct report 124.
Importantly, the commercially available bar code reader 110 and computer used to produce precinct report 112 operate independently of voting terminal 102 and report printer 114 used to produce precinct report 116. As such, referring to the comparison circle labeled as “A” in
In a similar manner, the commercially available bar code reader 110 and computer used to produce precinct report 112 operate independently of the election headquarter's software program and printer 120 used to produce precinct report 124. As such, referring to the comparison circle labeled as “B” in
Furthermore, referring to the comparison circle labeled as “C” in
While the present invention has been described and illustrated hereinabove with reference to an exemplary embodiment, it should be understood that various modifications could be made to this embodiment without departing from the scope of the invention. Therefore, the invention is not to be limited to the exemplary embodiment described and illustrated hereinabove, except insofar as such limitations are included in the following claims.
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