Utah gasoline prices hit record highs in five of the past seven days. And whenever gasoline prices spike � such as they do around every Memorial Day � arguments erupt about who is to blame. Politicians often call for investigations, as President Bush did after big gas price hikes last month.

Some politicians blame big oil companies and their big profits for big price hikes. Oil companies, in turn, blame politicians or environmentalists who limit new refineries and exploration. Some blame greedy Middle Eastern producers. Some blame taxes. Some blame lack of competition from recent oil industry mergers. Some blame local retailers or refiners.

Government investigations through the years reached an interesting conclusion about which of them is really to blame.

The answer: all of them. It's akin to "Murder on the Orient Express" where everyone on a train helped stab the victim. Pick a favorite suspect as the culprit for high oil prices, and you are essentially at least partially correct.

Here is what government investigations and studies have said about some of the major potential price villains — just in time for holiday motorists to know where to hurl gripes.

First, the good news

Before looking at possible gas villains, it is important to note that Utah has among the lowest gasoline prices

in the nation — up to 20 cents a gallon less than the national average at times in recent months, according to the Energy Information Administration data.

However, Utah gasoline prices finally pulled even with national averages on Thursday, as the state set record highs every day during the week.

Having gasoline that often is cheaper than the national average is good, since people in Utah bought about 1.4 billion gallons of gasoline last year and paid $2.2 billion for it (about $4,200 per licensed driver in the state), according to Deseret Morning News analysis of EIA data.

The main reason for that often-cheaper gas may lead residents to question why it is not even less expensive.

That reason is, in short: None of Utah's gasoline comes from the Middle East or other exotic places where wars or supply manipulation affect worldwide crude oil prices. Nor does it come from wells, refineries or delivery systems damaged by Hurricane Katrina.