Tourists who make it to the top of Diamond Head State Monument have been buying certificates from Christopher Barclay for years.

On Thursday, Barclay ended up taking home his own paperwork: a citation for soliciting and selling his certificates at Diamond Head without a required state permit.

Officers from the Department of Land and Natural Resources Division of Conservation and Resources (DOCARE) cited Barclay after watching him ask for $5 donations from tourists who wanted to take home a certificate saying that they had reached the top.

Barclay is just the latest person to be cited for unauthorized commercial activity, which has been an ongoing concern at Diamond Head. DLNR spokesman Dan Dennison said the department has given out numerous citations for unauthorized commercial activity at the monument. Barclay had previously been warned, Dennison said.

According to a cease-and- desist order, Barclay allegedly ran afoul of state law this time by using the flat surface of one of the bunkers at the summit as a table for commercial activity. The order also alleged that Barclay was misleading park visitors into thinking that he was affiliated with the state and using the proceeds to keep the park clean.

Dennison said commercial activities in state parks can be conducted only via a lease, permit or concession, usually authorized by the Board of Land and Natural Resources. Only two entities — the nonprofit Pacific Historic Parks and a food vendor — are currently authorized to do business at the park, he said.

The shop, which sells certificates for $2.50, pays a percentage of its gross receipts to the states parks division. The food truck vendor, which obtained its spot through a competitive bidding process, pays a fixed rate.

Division of State Parks Administrator Curt Cottrell said numerous people have asked the state to shut down unauthorized commercial activity at Diamond Head State Park.

“We have very specific rules regarding who can conduct commercial activities in state parks and under what circumstances. Bottom line, any commercial activity does require a permit, and Mr. Barclay has consistently refused to seek one,” Cottrell said.

Since Barclay was cited by DOCARE for a criminal violation of state rules, he will have to appear in Honolulu District Court. The criminal penalty for violating state park rules is a petty misdemeanor, Dennison said. Violators can face up to 30 days’ imprisonment and fines, he said.

DOCARE also could take the case to the Board of Land and Natural Resources, where civil penalties, including fines, may be issued, Dennison said.

Linda Wong, a member of the Diamond Head Neighborhood Board, said residents have spent years complaining to the board about unauthorized commercial activity in the park.

“It’s supposed to be a park for passive enjoyment. Unauthorized commercial use detracts from the experience,” she said.

Waikiki resident Stephany Sofos said authorities need to do a better job of reining in the growth of commercial activities on Hawaii’s public lands.

“I’m glad the state took action. I’d like to see the city crack down, too. We have similar issues at Kapiolani Park, where illegal surf schools and fitness classes are popping up. People who aren’t sharing in the upkeep and maintenance of these parks shouldn’t be able to use them for personal gain,” she said.