If you are caught carrying cocaine or cannabis in London, it does matter if you're black or white.
Figures show that black people in the capital are five times as likely to be charged than white people when they are caught with cannabis and nearly twice as likely to be charged when caught with cocaine.
The police statistics indicate 78% of black people found in possession of cocaine are charged rather than cautioned, whereas only 44% of white people are - making them nearly twice as likely to face prosecution.
People of Asian descent are also much more likely to be charged than white people - 64% of those caught with the Class A drug are charged.
With cannabis, black people are more than five times as likely to be charged than white people.
The Metropolitan Police data was collected by the authors of a joint report by the London School of Economics (LSE) and drug law reform charity Release.
The authors of the report say the racial disparity may be because of "negative stereotyping" on the part of the police.
They said the fact prosecutors abandoned a higher proportion of drugs possession cases against black and Asian people, after they were charged, backed this up.
Release executive director Niamh Eastwood, who presented the findings to the International Society for the Study of Drug Policy in Rome on Thursday, told The Huffington Post UK that the data suggested "some level" of bias on the part of the police, whether conscious or unconscious.
"It's important to remember our job was to show evidence, but it's fair to say that the data, particularly with the charging, shows some level of discrimination on the part of the police," she said.
The report noted some correlation between London boroughs which had the worst racial disparity in terms of charging decisions and the use of stop and search.
In Kensington & Chelsea for example, black people are five times more likely to be stopped and searched and 11 times more likely to be charged with cocaine possession than white people, if they are caught in the borough with the drug.
In Richmond-upon-Thames, black people were six times more likely to be searched and eight times more likely to be charged.
More than half of all stops and searches in London are for drugs, the report found.
One of the people interviewed for the report, a 46-year-old black man, said he was stopped and searched 10 times for cannabis between the ages of 16 and 21.
"All kinds of people take drugs, it is not limited to one race or class. I had to tell my son about the situation because of what I have been through, I had to tell him to be calm," he said.
"You need to understand that even though you know it’s wrong, you have no control, you just have to let them do what they are going to do. It is never going to change, my complaint isn’t going to do anything."
Eastwood told HuffPost UK that it was hard to say definitively what was behind the racial disparity.
She said: "I think it's very difficult to be sure what the causes are. Our aim was to show the problem and the impact of our drug laws on people from Black and Minority Ethic (BME) communities."
In a review of the report's data, independent fact checking organisation Full Fact said: "We know that London is not representative of the country as a whole. However, the city’s statistics, as presented by Release, are certainly striking.
"However, we do need to be a little cautious before concluding that this is evidence for the force being 'institutionally racist'."
The "institutionally racist" label has plagued the Met since the MacPherson Inquiry into the murder of black teenager Stephen Lawrence in the late 1990s.
In March, The Metropolitan Black Police Association, which speaks for the force's black officers, claimed the Met is still racist.
Chair Janet Hills said this was due to higher use of stop and search against black people and the underrepresentation of ethnic minorities in the force, especially in the senior ranks.
She told The Guardian: "For me, it lies in the fact there has been no change, no progression."
Eastwood described the race disparity in stop and search and drugs possession charging as "a significant source of discrimination".
The Met told HuffPost UK each person caught in possession of drugs is "dealt with according to the facts of the case".
"For an adult caution to be administered, the person needs to admit their guilt and have no previous similar offending history," the force said in a statement.
"When deciding whether or not to charge a person, there are a number of factors taken into consideration - such as no admission of guilt, previous offending history and amount of drugs in their possession.
"There also has to be a realistic prospect of conviction and be in the public interest."
Eastwood said a positive short term change would be for the police to stop treating "cannabis warnings" as "sanctioned detections".
Sanctioned detections effectively count towards police statistics as solved crimes and this incentivised police to go out and seek them in order to meet targets or satisfy their managers, Eastwood added.
A 2013 report revealed police in neighbouring Kent had been actively seeking out those they suspected of carrying cannabis so they could administer the warnings and drive up the number of sanctioned detections, amid their force's "target driven culture".
One of the LSE/Release report's authors went out on patrol with Met officers and was surprised how they immediately went looking for people to stop and search for cannabis.
"Well I need to get a sanctioned detection, this is a quick way to do it, and afterwards, if we get it now, I can spend the rest of the shift doing real policing," the officer said.