A few obvious drawbacks without even reading into the subject:
1) The additional sense of security may lead people carrying pepper spray to take more risks, to travel through more dangerous places, etc. (risk compensation, a la bicycle helmets)
2) Few people who carry pepper spray have received appropriate training in its use, and even those who are appropriately trained will take a not-insignificant amount of time to retrieve and effectively deploy it;
3) The person using pepper spray is almost certainly going to fall victim to the pepper spray themselves, hindering their escape from the attacker;
4) The use of pepper spray is likely to anger an attacker, leading to an escalation in violence; even if the attacker has difficulty seeing as a result of the spray, they may still inflict an awful lot of harm on their victim;
5) In the worst case scenario, in fumbling to retrieve and deploy pepper spray, it may be snatched by the attacker and used against the victim.
1) The additional sense of security may lead people carrying pepper spray to take more risks, to travel through more dangerous places, etc. (risk compensation, a la bicycle helmets)
2) Few people who carry pepper spray have received appropriate training in its use, and even those who are appropriately trained will take a not-insignificant amount of time to retrieve and effectively deploy it;
3) The person using pepper spray is almost certainly going to fall victim to the pepper spray themselves, hindering their escape from the attacker;
4) The use of pepper spray is likely to anger an attacker, leading to an escalation in violence; even if the attacker has difficulty seeing as a result of the spray, they may still inflict an awful lot of harm on their victim;
5) In the worst case scenario, in fumbling to retrieve and deploy pepper spray, it may be snatched by the attacker and used against the victim.