Shark Tank: Never depend on what users won't do

12.01.2006
Twenty-some police officers in this small town attend a mandatory training class in using a breath test machine, reports a pilot fish on the scene.

"It's to recertify their skills on the machine, which is used for measuring the blood alcohol level in people arrested for drunk driving," fish says.

"The class instructions are carefully worded to avoid ambiguity, and each of the students follows the instructions to the letter."

That's especially important when it comes to the "breath test refusal" section. In a real situation, if an arrestee refuses the test, the driver's license is automatically suspended.

Thus the instructions: Enter your own name as the arrestee. Enter your own name as the arresting officer. Enter all zeros in the field for the ticket number. Do not enter any criminal charges.

"This way, should the information somehow accidentally be forwarded to the Department of Motor Vehicles -- which it won't, because this is all computerized now -- the data entry clerk will realize something is wrong and flag the entry," says fish.