Philippine Sen. Leila de Lima shows documents asking the courts to dismiss cases against her during a news conference at the Senate in Manila on Tuesday. (Getty Images)

The leading critic of Philippine President Rodrigo Duterte's expansive crackdown on drug dealers is facing an arrest warrant on drug-related charges that she described as "simply surreal."

Sen. Leila de Lima is perhaps the loudest voice in the Philippines' opposition. She has taken aim at Duterte's drug war, which has led to the extrajudicial killings of thousands of suspects by state and state-sponsored militias. Human rights groups have documented more than 7,000 deaths since Duterte took power in June.

Last summer, as a presiding senator on a panel investigating the killings, de Lima presented a witness who claimed to have been a contract killer for Duterte. The senator was almost immediately demoted from the panel. In swift succession, salacious claims emerged about her sex life, along with allegations that she had taken bribes from drug dealers. Duterte cracked lewd jokes about de Lima in newspaper interviews and even went so far as to suggest that she commit suicide.

On Thursday, an arrest warrant was issued for de Lima, 57, over the allegations of bribery linked to drug dealers. The senator spent a few hours in her offices, where she was immune from arrest, before leaving and saying that she would say goodbye to her family before facing the charges in court.

Even after the arrest warrant was issued, de Lima, a former justice secretary, seemed to revel in her antagonistic relationship with Duterte. “I am ready to be arrested any time,” she told the Financial Times. “It’s actually going to be an honor for me to be in prison under this very repressive and oppressive regime.”

The charges against de Lima include soliciting and receiving money from jailed drug dealers to the tune of 10 million pesos (about $200,000). The alleged conduit for the money is her former driver, with whom she is accused of having an affair. Her first day in court will be Friday, and she has moved to have the case dropped entirely, claiming political vendetta.

Duterte's crackdown on drugs had broad popular support, as does the president himself. His brash way of talking and willingness to use violence even without legal backing has earned him a reputation as someone who can stand up to the gangs that have made drug addiction a critical issue in the Philippines.

On Thursday, Salvador Panelo, Duterte's legal adviser, welcomed the arrest warrant for de Lima, saying that "the law of karma finally caught up" with her.

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