Michael Gray, who police said worked with McRae in moving marijuana, pleaded guilty this week to conspiracy to distribute marijuana. He faces up to 20 years in federal prison, WJZ reported.
Since 2017, more than 200 packages were sent from California to a specific Baltimore ZIP code, all to addresses on McRae's route, the Sun reported.
Investigators intercepted some packages that came under suspicion. The contents tested positive for marijuana, WJZ reported.
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Two more boxes shipped from California were destined for the same address as the previous suspicious boxes. Instead of delivering the package to the address listed, McRae was seen by law enforcement surveillance giving it to a man who pulled up to his mail truck. The man was later identified as Gray.
One of the boxes was scanned as delivered at the time he gave it to Gray, investigators said.
Seven more boxes were slated to be delivered to the same address in January 2018, but they didn't get to the addressed destination. Gray has no connection to the address used for the drug scheme, WJZ reported.
Law enforcement intercepted and tested other packages that came up positive for marijuana but were repackaged and put back into the mail process. When Gray accepted the boxes from McRae, police arrested him.
Gray will be sentenced in September, WJZ reported.