Calibri font has "I" and "l" the same, according to Wikipedia. A better font should avoid characters being too similar (such as "I" and "l" and "1").
Another issue is due to the font size and font metrics, how much space it will take up on the page, to be small enough to avoid wasting paper and ink but also not too small to read.
So, there are multiple issues in choosing the fonts; however, Times New Roman and Calibri are not the only two possible choices.
Maybe the government should make up their own (hopefully public domain) font, which would be suitable for their purposes (and avoiding needing proprietary fonts), and use that instead.
replies(14):