Since his arrest last summer, Benton Mackenzie has maintained he grew marijuana to treat terminal cancer.

Now, just days ahead of going to trial Monday on drug conspiracy charges, a Scott County District judge has ruled he won't allow Mackenzie to use his ailment as a defense.

"I'm not allowed to mention anything," Mackenzie said Thursday, the day Judge Henry Latham's ruling was filed. "I'm not allowed to give proof why I was using. Now, there is no fair trial."

The 48-year-old, who shared his story with the Quad-City Times last September, was diagnosed with angiosarcoma in 2011. It's a cancer of the blood vessels, in which tumors appear as skin lesions.

He says the lesions have grown enormous since sheriff's deputies confiscated 71 marijuana plants from his parents' Long Grove home last summer. He needed all those plants just to be able to extract enough cannabis oil for daily treatments, he says.

Mackenzie wants to be able to tell jurors why he grew marijuana. He wants to show them pictures of his cancerous lesions.

"If I'm to tell the whole truth and nothing but the truth, and the court doesn't let me tell the truth, they're making me a liar," he said.

Assistant Scott County Attorney Patrick McElyea, who is prosecuting Mackenzie, filed a motion earlier this month to limit any testimony regarding medical marijuana. He has declined to comment on the case.

McElyea based his motion on the 2005 Iowa Supreme Court decision in State v. Bonjour, a case similar to Mackenzie's. Lloyd Bonjour, an AIDS patient, was convicted of growing marijuana, and the Supreme Court upheld the conviction.

Latham sided with McElyea's motion, stating, "The court is not aware of any legislation or been provided with any legislation which provides for such defense."

The judge states he is aware Mackenzie has angiosarcoma. He also is aware Iowa lawmakers recently legalized oil concentrated with cannabidiol, or CBD, with "specific restrictions."

The pending law, expected to be signed today by Gov. Terry Branstad, only applies to those suffering severe epileptic seizures.

Mackenzie says he thinks state government is the "bigger criminal," because it's practicing medicine without a license in deciding who can and who cannot possess medical marijuana.

"At least the state is now recognizing, with a law, that marijuana has medicinal value," he said, adding his plants were from a strain rich in CBD, which in other states is associated more with medical use than recreational use.

Without the medical necessity defense, Mackenzie said his fate is "completely in the Lord's hands."

Sitting through several hours of hearings over the past 11 months has been hard enough on someone with lesions covering his legs and rear, he says. He can't imagine sitting through an entire trial, which is scheduled to begin Monday with jury selection.

He says he may show up to court wearing a kilt, so jurors can see for themselves. But he wouldn't want his lesions oozing and bleeding all over the courtroom furniture.

"That shows how much of a criminal I'm not," he said.

At one point during a phone conversation with a reporter Thursday afternoon, he reacted because one of his larger lesions opened up and bled onto the chair and floor at home, he said.

"I'm sitting in a pile of blood," he said a moment later.

He wants to request a nurse or a medical provider be allowed to sit in the courtroom with him. He says the judge is allowing breaks, but he expects he'll have to take a break every few minutes just to replace the large, disposable underpad for furniture.

He anticipates that with his failing health and the number of co-defendants, the trial will come across as a "circus."

Mackenzie is charged with felony drug possession along with his wife, Loretta Mackenzie. His 73-year-old parents, Dorothy and Charles Mackenzie, are charged with hosting a drug house, and his son, Cody, is charged with misdemeanor possession. His childhood friend, Stephen Bloomer, also is charged in the drug conspiracy.

All six defendants are being represented by a different attorney.

Lately, Mackenzie's health has been "touch and go," he says, with episodes of vomiting, cold sweats and extreme pain. He almost always feels tired.

He raised enough money from family and friends to travel twice this spring to Oregon, which has legalized medical marijuana.

Each trip was a week long. During the first trip, he met with a physician, who approved him for a state medical marijuana identification card. On the second trip, he was able to purchase oil in an amount equivalent to a pound and a half of marijuana, which he couldn't by law bring back to Iowa.

The little bit of relief is nothing compared to the daily treatments prior to his arrest, when he was shrinking his skin lesions, he said. He claims the oil in Oregon also stopped the growth of the lesions, but only temporarily.

Mackenzie said he hopes jurors will show compassion in deciding his future.

"No matter what, if I'm found guilty, I'll do at least three years in prison, which is a death sentence for me," he said. "If I'm found guilty at all, I'm a dead man. I'm lucky I'm not dead already."