He asked riders to allow him to test them, promising secrecy. The results helped create the first doping law. The first routine examination of all sports in the Olympic Games started in Grenoble and Mexico in 1968. Dumas gave his first public warning about doping during the 1962 Tour de France, when 12 riders fell out sick in a single day, many of them from the same team. The riders and their officials insisted they had eaten bad fish at their hotel. The hotels proved that they hadn't. Dumas concluded that they had taken a badly administered cocktail that included morphine, a pain-killer. He and Robert Boncourt, his colleague on the amateur race, the Tour de l'Avenir, warned in the press about drug-taking and its dangers. It was the first time an official of either race had made a public statement of the sort and next day the professional race came close to a strike. The incident led Dumas and Boncourt to organise a conference on drug-prevention at Uriage-les-Bains the following year. That brought France's first law against drugs in sport, passed shortly after a similar law in Belgium. On 1 June 1965, France passed Law 65-412, known as the "Loi Herzog", after Maurice Herzog, the minister of youth and sport. It led to a spot test on the 1966 Tour de France, after which riders went on strike and called for Dumas to take a test himself, to see if he had been drinking wine or taking aspirin to make his own job easier. "The implication was clear," said the British writer Geoffrey Nicholson. "Any more testing, no more Tour." The penalty threatened by the law, said Nicholson, was "up to a year's imprisonment and a fine of roughly £400", but "in France, this law was not enforced, mainly it seemed because professional cyclists regarded it as an intrusion on their personal liberty, and on the whole public opinion was behind them." The UCI had not been enthusiastic about drug-testing. William Fotheringham wrote: (In 1962), cycling's international governing body, the Union Cycliste Internationale, had thrown out a motion from the Polish federation to make the UCI responsible for combating doping. Measures against the use of drugs in cycling, when they came, were led by the police in Italy, Belgium, Switzerland and France. They treated action against sportsmen as an extension of their operations against drug traffickers and behaved accordingly. Early anti-drug operations at cycle races were crude, did nothing to make cyclists feel well-disposed towards their imposition, and lacked any credibility.