Police on Wednesday said the blood test conducted on businessman Suthat Siwapiromrat found a level of alcohol in his blood lower than the illegal amount. However, the test was conducted more than three hours after the crash, which occurred at 12.30am.
Blood alcohol levels can fall swiftly .
Suthat is an executive at seven companies and a well-known political donor.
The test – conducted sometime after 4am at Police Hospital – found that his blood alcohol level was 20 milligrammes per 100 mL, lower than the legal limit of 50 mgs per 100 mL of blood.
The accident occurred at 0:30 am on Sunday on Chalerm Mahanakhon expressway.
Police said Suthat had driven about nine kilometres from Suksawat to Din Daeng before rear ending a Pajero SUV that was carrying six members of a family. The force of the crash caused the SUV to overturn. Four members of the family inside it were injured.
Suthat refused a breathalyser test at the scene, sparking irate comments on social media accusing police of being lenient with the millionaire.
However, Maj Gen Jirasan Kaewsaeng-ek, deputy commissioner of the Metropolitan Police Bureau, had a more generous explanation. He said Suthat was suffering chest pains that were so severe he lacked the strength to blow into the device that detects alcohol in the breath.
As a result, police took him to the Police Hospital for a blood test at 4am.
This caused more criticism on social media as citizens accused police of helping Suthat avoid drunk-driving charges. Some posts noted that blood alcohol rates can drop between 15 to 20 mgs per 100 mL of blood per hour.
Since his blood was tested more than three hours after the crash, his blood alcohol rate could have fallen by 45 mgs per 100 mL. Consequently, his alcohol blood level may have been higher than the legal limit when he plowed into the SUV, social media commentators said.