FILE - In this June 28, 2012 file photo Rep. Andy Harris, R-Md., speaks at a news conference outside the US Capitol in Washington. As immigration advocates swarm the country trying to persuade House Republicans to pass a comprehensive immigration overhaul, Harris held a town hall meeting this August northeast of Baltimore, Md., with an overflow crowd who booed loudly when an audience member asked him to support a path to citizenship for immigrants in the U.S. illegally. Harris shot the idea down calling it a "nonstarter" that's "not going anywhere fast" in the House. (AP Photo/Cliff Owen)

WASHINGTON -- If there's one thing Rep. Andy Harris (R-Md.) wants you to know about his crusade to block the District of Columbia's marijuana decriminalization statute -- which officially went into effect on Thursday -- it's this: He's doing it for the kids.

"There is no question in anyone's mind, nor should there be, that teenage drug use will go up due to D.C. decriminalization laws," Harris said on Bill Bennett's radio show this week.

In fact, studies show that scholars are not nearly so unequivocal on the question of whether decriminalization or similar laws lead to more teenagers using the drug.

A spokeswoman for Harris referred The Huffington Post to a statement from the American Academy of Child and Adolescent Psychiatry opposing decriminalization, which the group warns is "likely to be associated with" increased teen pot use.

But other researchers have concluded that fewer legal barriers to marijuana use -- either through the legalization of medical marijuana or the lowering of penalties for pot possession -- do not cause the young to flock to the drug at higher rates. A report from the Institute for the Study of Labor found that over the years 1993 to 2011, teen marijuana use actually dropped in states that legalized medical marijuana.

That report also noted that only two previous studies had looked at teen use following the legalization of medical marijuana: One found a slight increase; the other found a decrease.

Furthermore, when all drugs were decriminalized in Portugal in 2001, drug use decreased among teenagers, according to a Cato Institute analysis by Glenn Greenwald. Under Portugal's new system, the rate of lifetime marijuana use for teenagers in 10th-12th grade fell from 27.6 percent in 2001 to 21.6 percent in 2006. It also fell for teens in lower grades.

Harris, however, has been adamant that decriminalizing or legalizing of any form of marijuana will have only one result. "Even medical marijuana legalization increases drug use," he said on Bennett's "Morning in America" show. "You can't take any step at all because where you end up, it's going to be inevitable and it ends with increased drug use."

Asked last month for clarification on Harris' position, his spokeswoman Erin Montgomery said, "Passing marijuana decriminalization bills for teens is not the way to lower D.C.’s high rate of drug abuse among teens and definitely not the way to deal with skyrocketing teen unemployment in the District, especially among minority youth."

Marijuana advocates argue, however, that legalizing the drug could have benefits related specifically to teen pot use. Tom Angell, chairman of Marijuana Majority, said that "legalizing and regulating the marijuana trade allows for age restrictions to be enacted and enforced."

Angell pointed to sting operations in Colorado, where recreational marijuana was legalized earlier this year, as evidence that age restrictions can be properly monitored and enforced. When Colorado officials sent underage shoppers into 20 different stores selling marijuana, none was able to buy the drug.

Another activist argued that Harris' views on the sale of alcohol are apparently at odds with his views on marijuana.

"Scientific research and government reports have concluded that marijuana is less addictive than alcohol, less damaging to the body and less likely to contribute to violent and reckless behavior," said Mason Tvert, director of communications for the Marijuana Policy Project. Yet, Tvert added, Harris "has gladly accepted thousands of dollars in contributions from those who distribute it [alcohol] to Americans."

Harris' efforts to block D.C.'s new pot policy began in June, when he attached an amendment to an appropriations bill that would bar the District from spending any money on efforts to lessen the penalty for marijuana possession. (The appropriations rider is a strategy that congressional Republicans have routinely used to meddle with the city, which doesn't have final say over its own criminal laws.) The Maryland lawmaker has drawn sharp condemnation from many D.C. officials and the District's non-voting representative in Congress, Del. Eleanor Holmes Norton (D).

Speaking on the House floor late last week, Norton lambasted Harris for trying to "bully" her constituents. "You will occasionally hear members say something only a tyrant would say," Norton said. "Rep. Andy Harris was unable to convince his own state not to decriminalize marijuana, so he steps across the border into the District of Columbia to try to tell us what to do?"

Harris' effort seems to run in opposition to the current bipartisan push to change the way non-violent drug offenders are punished. Earlier in July, Sens. Cory Booker (D-N.J.) and Rand Paul (R-Ky.) teamed up to introduce the REDEEM Act, aimed at reforming the criminal justice system as it pertains to teens and non-violent offenders, including anyone convicted under drug possession laws. On Friday, the U.S. Sentencing Commission elected to make new sentencing guidelines for federal drug-related offenses retroactive -- a move that will affect about 50,000 individuals.

The District's local decriminalization measure passed earlier this year, with support from many D.C. residents. Its main sponsor framed it as an issue of racial justice, citing studies that showed up to 90 percent of those arrested for possession in the city are African-American.

Norton similarly noted last week that decriminalizing marijuana would help teens, particularly blacks who are four times more likely than whites to be arrested for possession in D.C. despite relatively equal use across racial lines.

"Do you know what that means for a young black man or boy in this country today? It ruins their lives," Norton said on the House floor. "An arrest or a conviction of any kind for 'drug possession' … can lead a young man in the District of Columbia to the underground economy, even to selling drugs from where he was only possessing them before, because he can't find a job because he's got a 'record.'"