On MSNBC, Brzezinski and Novotny falsely asserted McCain's gas tax plan would eliminate "20 percent of the cost"

Summary: On MSNBC Live, Mika Brzezinski said that Sen. John McCain "wants to eliminate the federal gas tax -- that's about 20 percent of the cost." Later, Monica Novotny said McCain is "proposing suspending the federal gas tax for the summer, potentially cutting prices by nearly 20 percent." In fact, the federal gas tax -- 18.4 cents per gallon -- comprises only 5.4 percent of the current average cost of regular gasoline.

On the 9 a.m. ET hour of MSNBC Live, host Mika Brzezinski said that Sen. John McCain "will lay out a new plan to help Americans deal with high gas prices. From Memorial Day to Labor Day, McCain wants to eliminate the federal gas tax -- that's about 20 percent of the cost." Similarly, on the 10 a.m. ET hour of MSNBC Live, host Monica Novotny said McCain is "proposing suspending the federal gas tax for the summer, potentially cutting prices by nearly 20 percent." In fact, the federal gas tax does not represent 20 percent of the cost of gasoline. The Department of Transportation's website notes that the federal gasoline tax is 18.4 cents per gallon. The U.S. Department of Energy's Energy Information Administration (EIA) reported on April 14 that the average price of regular gasoline nationwide was $3.389 per gallon, meaning that, on average, federal tax comprises 5.4 percent -- not 20 percent -- of the current total cost of regular gas.

According to a chart produced by EIA, federal and state taxes combined represented an average of (state gasoline taxes vary by state and fuel type) 13 percent of the cost of gasoline in February, when regular gasoline was $3.03 a gallon.

As Media Matters for America noted, on the April 1 edition of MSNBC's Hardball, host Chris Matthews wrongly suggested Sen. Barack Obama was exaggerating the price of gasoline when Obama reportedly noted a friend's complaint that it cost "$85 to fill up my tank."

From the 9 a.m. ET hour of the April 15 edition of MSNBC Live:

BRZEZINSKI: Less than an hour from now, John McCain will lay out a new plan to help Americans deal with high gas prices. From Memorial Day to Labor Day, McCain wants to eliminate the federal gas tax -- that's about 20 percent of the cost. [Sen.] Hillary Clinton will take some time off from the campaign trail to hit Comedy Central's The Colbert Report this Thursday.

From the 10 a.m. ET hour of the April 15 edition of MSNBC Live:

NOVOTNY: Meanwhile, a new poll out of Pennsylvania shows Hillary Clinton holding up on her lead. She's still up by six points, 50 percent to 44 percent, the same margin as a week ago. And John McCain says he's got a plan to help drivers. Today, he's proposing suspending the federal gas tax for the summer, potentially cutting prices by nearly 20 percent.

And we'll have much more on politics in a moment, but first to that government raid at a polygamist retreat in Texas.

—B.J.L. & A.C.S.