Michele Leonhart, the head of the Drug Enforcement Administration, ducked a tough line of questioning from Rep. Jared Polis (D-Colo.) on Wednesday, refusing to answer a number of questions about the comparative health impacts of marijuana and other, harder drugs.

Leonhart was testifying before the House Judiciary Subcommittee on Crime, Terrorism, and Homeland Security. Polis, a top congressional advocate for marijuana law reform, took the opportunity to grill the DEA administrator on some specifics about marijuana, which has been decriminalized in some parts of his state and legalized for medical purposes in the rest.

Is crack worse for a person than marijuana? Polis asked Leonhart.

I believe all illegal drugs are bad, Leonhart answered.

Polis continued, asking whether methamphetamines and heroin were worse for a person's health than marijuana.

Again, all drugs, they're illegal drugs, Leonhart started, before being cut off by Polis.

Yes, no, or I dont know? Polis said. If you dont know, you can look this up. You should know this as the chief administrator for the Drug Enforcement Agency. Im asking a very straightforward question: Is heroin worse for someone's health than marijuana?

Leonhart ducked again, repeating, "All illegal drugs are bad."

Since assuming the head position at the DEA, Leonhart has made controlling prescription drug abuse the top priority, a stance she had laid out so aggressively that it led one Democratic senator to block her confirmation .

Asked by Polis whether prescription drugs were more addictive than marijuana, Leonhart again skirted the question.

"All illegal drugs in Schedule I are addictive," she said, before avoiding a question about whether prescription pills were more harmful than marijuana.

Leonhart has been a controversial figure in the drug policy reform community since she was named acting administrator of the DEA in the wake of her predecessor Karen Tandy's departure.

While her opponents in the marijuana policy reform community were particularly upset at her nomination, due to suggestions that she would ignore an earlier announcement by the Obama administration about making marijuana crackdowns a low priority, she also ran into trouble when reports surfaced that DEA officials had become entangled in a Ponzi scheme .

Despite these concerns, she was eventually confirmed by a unanimous vote in late 2010. Meanwhile, the Obama administration's previous pledge to deemphasize marijuana enforcement appears to have gone by the wayside .

Watch the whole exchange, via Polis' YouTube page :

UPDATE:

Reddit user Glambattista flags a separate exchange from Wednesday's hearing in which Leonhart faces another round of aggressive questioning on marijuana from Rep. Steve Cohen (D-Tenn.).

Below, where medical marijuana has been legalized in the United States:

CORRECTION: In an earlier version of this article, Michele Leonhart's name was misspelled. We regret the error.