Legislation to crack down on club drug use is wrapped in a popular child safety package, but critics worry that businesses whose customers use drugs without the proprietors' knowledge could face prosecution under the measures being signed into law Wednesday.

"You could have hotels prosecuted, you could have sporting events prosecuted, basically anything or anywhere you could expect someone to try and use drugs," said Marvin Johnson, an American Civil Liberties Union lawyer.

Bush was signing the Amber Alerts (search) package, which has as its centerpiece a voluntary rapid-response network to help find kidnapped children, on Wednesday.

It includes legislation originally introduced as the RAVE Act (search) - or Reducing Americans' Vulnerability to Ecstasy Act - that was aimed at "club drugs" like Ecstasy.

An earlier version targeting drugs found at raves, concerts and other venues frequented by young people failed to pass Congress last year, after complaints that the bill unfairly painted all raves and concerts as havens for illegal drug use.

The bill was modified to take out its original focus on raves, renamed the "Illicit Drug Anti-Proliferation Act," and placed inside the Amber Alert bill.

Opponents say broadening the focus makes the bill more dangerous.

"Our concern is this law is so wide and so vague that prosecutors are going to find it easy to apply it to just about anyone," said William McColl of the Drug Policy Alliance (search), an independent drug policy reform group which promotes alternatives to the war on drugs.

The legislation is based on the federal "crackhouse" statute, which allows prosecution of people who knowingly allow their private residences or businesses to be used for the buying and selling of drugs. The new provision would expand the statute to include places rented for temporary or one-time events like nightclubs, concerts or raves.

Lawmakers who supported the popular Amber Alerts package said they understood the concerns.

"Business owners have come to Congress and told us there are only so many steps they can take to prevent any of the thousands of people who may attend a concert or a rave from using drugs," said Sen. Patrick Leahy of Vermont (search), the top Democrat on the Senate Judiciary Committee. "They are worried about being held personally accountable for the illegal acts of others. ... Those concerns may well be overstated, but they deserve a fuller hearing."

One of the sponsors of the law, Sen. Joseph Biden, D-Del., (search) told the Senate earlier this year that its burden of proof is high enough that innocent businesses won't be affected.

"The purpose of my legislation is not to prosecute legitimate, law-abiding managers of stadiums, arenas, performing arts centers, licensed beverage facilities and other venues because of incidental drug use at their events," Biden said.

One industry representative is satisfied that the bill as it stands protects businesses.

"Enough changes have been made to the bill that legitimate law-abiding nightclub owners should be protected," said Darren Spinck, spokesman for the American Beverage Licensees, which represents bars and clubs in 33 states and the District of Columbia. Still, Spinck said he would like to see businesses protected with greater specificity.

People convicted under the law would face prison terms or civil fines of up to $250,000 or twice the gross revenue of their particular event.