B&J watched for police cars

Dorian Johnson told investigators that while walking north on West Florissant Avenue, he and Brown saw two police cars, one of which stopped at the McDonald's restaurant. Johnson figured that neither police officer had been informed about the robbery of the Ferguson Market and Liquor store. 

Johnson As we're walking down West Florissant, leaving the store, I heard the man [Market clerk] say that he would call the police, and it kind of threatened me. It got me nervous.

We still are not running [or] fast-pace walking. We still [are walking at the] same pace [as when we had been walking] to the store. We walk in front of the store just as normal and calm in plain day.

We [have] not even fully passed McDonald's. We're not on the same side of the store [Ferguson Market] any more. We crossed right in front of the store. ....

Upon the time walking on West Florissant, I saw police cars. It made me a little nervous, because I thought he [the store clerk] just called the police.

The strangest thing happened, though. None of the police cars we saw driving down West Florissant even stopped at the store. One [police car] stopped at McDonald's. .....  

One [police car] kept going, and I didn't really pay attention to where the other one going. 

I know for sure they didn't stop at the store. 

So that's when I figured that he [the Market clerk] probably try to scare us, because I don't think he made the call at all.

Detective He [the clerk] is bluffing you.

Johnson  That's what I thought.

[Pages 8 - 9; emphasis added]

As Brown and Johnson walked northward, they continually looked for police cars and frequently looked backward toward the Market. They did see police cars twice. On those occasions, they could briefly move off of the sidewalk so that they would not be noticed by the police officers. 

Brown and Johnson might have been walking past the Northland Chop Suey restaurant when they saw the first police car, which eventually "stopped at McDonald's". They could have hidden briefly behind that business so that the patrol officer did not see them. 

Another possibility is that they entered the gate of the Shopping Center Services compound, which was surrounded by a fence. 

(Shopping Center Services is located at 9292 West Florissant Avenue, Ferguson, Missouri, and you can study that area by searching for that address on GoogleMaps.com)

Brown and Johnson might have hidden
behind the Chop Suey restaurant
or inside the SCS fence.

Brown and Johnson exited the Market at 11:52:15
and perhaps were passing Northland Chop Suey
or Shopping Center Services at 11:55. 

Since neither of the two police cars seemed to go to the Market, Brown and Johnson decided mistakenly that the Market clerk had bluffed them about the police being called.

-----

When Brown and Johnson saw the police car stop at McDonald's, they did not realize that it had stopped already at the Market. They did not see the police car until it turned north onto West Florissant Avenue, and then they saw it turn west into the McDonald's parking lot. 

Brown and Johnson saw Policeman McDonald
drive into the McDonald's parking lot

That police car was driven by an unidentified police officer, whom for the sake of convenience I name Policeman McDonald. He was looking for a Black male wearing a white t-shirt and walking north (toward the QuikTrip store). At 11:55, he sent a radio message saying that he did not see anybody wearing a white t-shirt and walking north. 

Brown and Johnson did not turn east onto Canfield Drive until 11:56.

My explanation for Policeman McDonald's failure to see Brown and Johnson was that they were looking around and behind themselves as they walked, and they  hid off the sidewalk briefly as soon as they glimpsed the police car.   

Policeman McDonald circled around behind the McDonald's restaurant and returned to the Market. There, he asked the clerks for more details about the culprit. Then he got back into his police car and sent a radio report to the police dispatcher at 11:57:47. He said that the culprit was wearing also a red baseball cap and yellow socks, was walking with another male, and was walking toward the QuikTrip store. 

Perhaps Brown actually mentioned the QuikTrip store to the male clerk during the cigarillo transaction. Policeman McDonald told the police dispatcher that the culprits were walking toward the QuikTrip, and then he drove to that destination.  

I estimate that Policeman McDonald passed the intersection of Canfield Drive at about 11:58:30. If so, Brown and Johnson already had been walking east on Canfield Drive for about 2½ minutes. It's possible that they happened to look back and glimpsed Policeman McDonald drive through the intersection, north to the QuikTrip. If so, then this glimpse would account for the second police car that Johnson mentioned in his testimony. 

Brown and Johnson saw Policeman McDonald
driving toward the QuikTrip store

Another possible explanation for Johnson's mention of a second police car is that he might have seen some car that looked like a police car. For example, Johnson might have seen a county sheriff's car, a parking-enforcement car, or a police car from some other jurisdiction.