Hurricane Ike made landfall overnight on Sept 12/13, 2008. In the days before that, there were reports of gas price gouging and governors of several states declared states of emergencies which put anti gouging laws into action. Four of these states were North Carolina, South Carolina, Arkansas, Alabama, and Tennessee.
I went to minnesotagasprices.com and plotted some data to see the what happened to gas prices in those states. For reference, I add gas prices in Oklahoma and Texas, two states that have not been active in going after so-called gougers. I also add the price of a barrel of crude oil to standardize the look of the graphs. Here's the screen shot from 5:10 PM on 9/15 for Texas, Arkansas, and Oklahoma.
Click on the image for a larger version. Even though crude oil prices have fallen, the price of gasoline rose in all three states as Ike neared the Gulf coast. But the price increase was higher in Arkansas that in Oklahoma or in Texas.
Here is the plot for North Carolina, South Carolina, and Texas taken at 6:44 AM on 9/15.
The average price of gasoline rose in all three states, but it spiked in North Carolina and South Carolina. Texas was directly hit by Ike, the Carolinas were not.
Here is a plot for Houston, Knoxville, Tn. and Mobile, Al. taken at 5:03 PM on 9/15. All cities saw the average retail price of gasoline increase, but it spiked in Knoxville (and there were reports of shortages). The average price of gas rose faster in Mobile than in Houston.
Lastly, here's Houston, Charlotte, NC, and Columbia, SC taken at 5:14 PM.
Similar story. Gas prices rose in all three cities, but they spiked in the two Carolina cities.
What seems to be the lesson here regarding these particular price spikes? Aside from the other effects of Hurrican Ike, effects that also drive prices higher, it seems that the gas price gouging laws impose an added cost on gasoline retailers: a potential fine that they'll have to pay if they are deemed to have increased their prices "too much" (as well any expected costs of defending themselves). The result is less gasoline on the market and higher prices to consumers than in the absence of the gouging laws, all else equal. It seems that instead of keeping gas prices low, they actually drive gas prices higher in states of emergencies.