Last month, CU-Boulder announced that it would be closing campus on 4/20 for the second consecutive year -- and attorney Rob Corry, who unsuccessfully challenged the shutdown in 2012, is encouraging Boulderites to take part in Denver's 4/20 rally.

If many of them do so, CU-Boulder could be quiet this weekend. But the campus police force will still be ready for challenges -- including a Friday Macklemore concert that may be prompting more visitor-pass requests than potential protests.

CU-Boulder police spokesman Ryan Huff says that from a law-enforcement perspective, the department's approach "will look very similar to last year" -- meaning that access to the campus will be restricted to students, staff and those who have received visitor passes because they have business on campus Saturday.

The main difference? According to Huff, "Officers will have index cards that will describe why the campus is closed for the day, why the administration has asked us to be there, and what people could face if they go onto campus if they don't have student, employee or visitor credentials. And there's going to be an e-mail address for the Vice Chancellor for Administration and also a website" -- Colorado.edu/april20, which is already live -- "for more information."

The latter has been added to the mix, Huff notes, "because we got some feedback last year that there wasn't a great avenue to offer complaints, praise, suggestions, comments. So there'll be some additional methods so that people can provide that feedback."

The goal "isn't to put one of those cards into every person's hand," he allows. "But if they have questions -- if they wonder why the campus is closed -- these cards will have all that information on them."

Huff doesn't expect that particular question will come up much given the amount of press the closure has already received, not to mention social-media outreach conducted by the university in the weeks since the announcement. Like last year, moreover, there will be signage on routes leading to the university, as well as along the perimeter of the campus, letting people know that on April 20, CU-Boulder is closed to unauthorized visitors.

Brittni Hernandez, president of Colorado University Student Government, or CUSG, advocated strongly for the cards, as well as for CU-Boulder Police to be aware that some transgender students may not look like the photo on the campus ID cards they'll be asked to show when coming onto campus. Huff says "we don't foresee that being an issue. Our officers are certainly going to be sensitive to that."

As for the question of how many people have applied for visitor passes, Huff puts that number at around 100 -- a very modest total if a group planned to infiltrate the campus for reasons of protesting the closure or staging an authorized 4/20 protest. Not that there are prominent indications such an effort is in the planning stages. "We've seen some traffic on social media about various protests or marches, and we're monitoring that," Huff emphasizes. "But we haven't seen anything to indicate that there will be a large-scale demonstration."

Then again, most of the people who've applied for visitor passes appear to have another event in mind.

Continue for more about the CU Boulder campus closure on 4/20, including photos from last year. "On Friday, the night before April 20, there's a Macklemore concert, and we've heard from a number of students who are bringing their friends on campus for it," Huff says.

Macklemore, by the way, is not only hugely popular right now, but he also happens to have an anti-drug message.

The concert isn't the only thing happening at CU Boulder this weekend. As Huff puts it, "There are a variety of other campus events that are going on where people who are not necessarily affiliated with the university have official business to be on campus."

Those who do have permission to be there won't have to surrender their free speech rights, Huff emphasizes. "If people are simply protesting and exercising their First Amendment rights and they're students, employees or approved visitors, that's their constitutional right to do so."

The only exception to this rule is Norlin Quad, traditionally ground zero for CU Boulder's 4/20 event. Last year, the patch of greenery was spread with foul-smelling fish fertilizer intended to keep people off the grounds, but due in part to complaints shared by CUSG, the university has decided to forego the stuff in 2013. However, Huff confirms that the quad will still be taped off, with students, employees and visitors all restricted from being there on Saturday.

Where should they go instead? Huff has some ideas. "There are a number of events going on in Denver and at Red Rocks on that day, and they seem to be gaining popularity," he says. "So there are alternatives for people who want to celebrate that day."

Meanwhile, Huff hopes year two of the 4/20 closure goes as smoothly as did year one. "We were pleased with how things went," he says. "We hope again for peaceful interactions. There were no confrontations with the public, and we definitely appreciated the public's cooperation. There were no complaints about police, no confrontations, no injuries. And we would hope for a similar interaction this year."

Continue to see images of 4/20 at CU-Boulder last year by photographer Britt Chester. Continue to see more of Britt Chester's photos from 4/20 at CU-Boulder last year. Continue to see more of Britt Chester's photos from 4/20 at CU-Boulder last year.

More from our Education archive: "4/20 at CU-Boulder: Rob Corry explains why he won't challenge campus closure."

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