In the case at issue, the evidence to be examined consisted of 29 pages of a cash book that contained payment entries that were numbered and dated by hand using blue ballpoint-pen ink. Investigators suspected that the cash-book entries might have been made over a short period of time and then backdated, rather than being entered on the date indicated. The document lab of the Zurich Canton Police (Switzerland) was asked to determine the date of the entries. The issues of interest were whether the cash-book entries had been made consecutively during the period of 1 year and whether the document could have entries made in 2003 and then backdated to 2000. Electrostatic detection apparatus (ESDA) was performed prior to destructive ink analysis on each page in order to gain the visualization of indented impressions. This was done to indicate whether the writings occurred at one or multiple sittings. Samples of the ballpoint-pen ink were then subjected to HPLC analysis to determine the ink types and the state of decomposition that began when the ink was transferred from the pen to the paper. Although small dating irregularities were detected by ESDA, the HPLC analysis concluded that there was no large volume of backdating of entries made at one recent sitting. 4 figures and 7 references