Speed traps can ruin a summer road trip. It's not just the cost of the ticket that makes your blood boil; it's also that feeling that you're being targeted for being an out-of-towner, seen as a cash cow for a cash-strapped county.

Most of us just grin, bear it, and try to move on. But according to a report in the Wall Street Journal, one U.S. tourist visiting from Spain was so outraged by police conduct in Springdale, Utah, she filed a complaint. And now that complaint has triggered a potentially damning audit of the local police department.

The fateful event

In October of last year, an unnamed Spanish tourist was driving through Springdale, probably on her way to the spectacular Zion National Park nearby. She was pulled over for speeding -- which would've been no big deal, had the police officer not then demanded that she pay him the fine immediately, in cash.

But this tourist was no chump. She filed a complaint with the state of Utah, which set off an investigation led by Utah State Auditor Auston Johnson.

Findings

Preliminary results from Johnson's investigation have uncovered a total of $11,640 in fines collected from foreign tourists during the first ten months of 2011. The actual figure could be much higher, since roughly 1/3 of the citation documents Johnson examined were missing, meaning that those citations could've been written and subsequently destroyed after tourists made their payments, leaving cops to pocket the cash.

Of course, it's important to note that in smaller towns, it's not uncommon for law enforcement agents to demand immediate payment of traffic fines. That's particularly true when the speeders are foreign nationals, who may be difficult to track down later.

What makes the case in Springdale so unusual is that the agents were collecting cash themselves rather than referring people to the local traffic court. There was no opportunity for appeal, which makes these stops look one step shy of a shakedown.

According to Springdale city officials, the police had an agreement with the courts that allowed them to collect fines. However, Johnson has no record of such an agreement.

Springdale's chief of police, Kurt Wright, says that the department has now stopped accepting cash, upon the auditor's recommendation. However, he also says that an internal investigation has cleared his officers of any wrongdoing.

Bottom line: whether you're spending your summer vacation in Zion or on the Zuiderzee, be on the lookout for speed traps -- and be sure to share any interesting stories with us. (That goes for you law enforcement agents, too.)