Sometimes, when a big new issue presents itself, such as a deadly disease epidemic, lawmakers must respond on the fly. They craft laws without knowing the full facts, taking a gamble on the unintended consequences.

When it comes to legalizing recreational marijuana in Illinois, precisely the opposite is true. There is no compelling reason to rush a decision, and plenty of reasons not to.

EDITORIAL

To be precise, there are nine excellent reasons not to — eight states plus the District of Columbia, where recreational pot already has been legalized. They offer Illinois a terrific opportunity to sit back, watch and learn. The benefits and dangers of legal pot will become more clear fairly quickly, at which time Illinois can proceed accordingly.

In Illinois, two state legislators are proposing to legalize recreational marijuana for people 21 or older. Users would be limited to possessing about an ounce or less and could not drive under the influence of the drug. Lighting up in public would be banned.

That sounds reasonable enough, and we certainly understand the attraction of more taxable revenue for our financially troubled state. But skeptics continue to warn of the dangers, such as the potential physiological effects and the questionable message sent to young people about the casual use of drugs.

Far better, then, to take a breath. Let’s see how recreational marijuana plays out in, say, Colorado or California. We might also learn a few things from Canada, which is expected to legalize recreational pot soon.

If access to recreational pot were a fundamental matter of civil rights, Illinois would be wrong to delay legalization any further. But it is not. The urgency does not rise to the level of, say, legalizing same-sex marriage or eliminating unconstitutional barriers to voting.

Canada already has identified some concerns about recreational marijuana that Illinois would have to address. Testing equipment similar to breathalyzers must be developed for marijuana, to guard against increase in impaired drivers. The testing equipment also would have to be made available to many workplaces, such as factories, to safeguard against workplace accidents. Concerns remain whether young people would have easier access to a drug that some scientists warn inhibits brain development.

Taking a wait-and-see approach also will allow lawmakers to see how the Trump administration’s plans to enforce federal laws against marijuana play out. The Obama administration’s policy was to avoid interfering with state legalization of non-medical marijuana use. States can’t count on that anymore. Conflicts between federal and state could create huge legal headaches.

The strongest argument for legalizing recreational pot in Illinois right now is money. Last year, the state of Colorado pocketed nearly $200 million in tax revenue from recreational marijuana. State Sen. Heather Steans and state Rep. Kelly Cassidy, Chicago Democrats, who are pushing legalization in the General Assembly, expect Illinois would pull in between $350 million and $700 million a year. In one fell swoop, our state’s finances would be in much better shape.

But then there is this, again giving us pause: The National Institute on Drug Abuse says marijuana impairs judgment, reaction time and motor coordination. If more motorists use marijuana, more people could die on our highways.

A legitimate worry? Or anti-pot alarmism?

We don’t know and don’t have to guess. The answer to that question — and many others — will be coming soon enough from those eight other states, the District of Columbia and Canada.

Each is a laboratory studying the social and medical impact of recreational pot.

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